The Houses of Parliament - an iconic London site that attracts visitors from all over the world.

Tourism is now worth 22.1 billion pounds (32 billion US dollars) annually to the UK, according to Visit Britain, Britain's national tourism agency.

Visit Britain also said that last year there were 36.1 million tourist visits, with 67 percent from the European Union.

On 23 June, the UK will vote in a referendum whether to stay in or out of the EU and many in the tourist industry are concerned that a possible leave vote will jeopardise the European holiday market.

One of those is Kyle Haughton, managing director of City Cruises.

His cruise ships carry 6 million passengers a year - in the height of summer 60 percent are from abroad, the majority from the EU.

Of the 240 staff that he employs, 50 percent are from outside the UK, mostly from the EU.

"Any change or decline in passengers coming into the country is going to affect our business quite lot and there are reports that people in Germany, Italy and France are less likely to come to the UK if we leave the EU than if we stay."

His fears are backed up by UK Inbound, which represents 360 tourist businesses.

Deidre Wells, chief executive of UKinbound has called leaving the EU "economic suicide."

"Why would you remove yourself from a market that provides two thirds of our business for our members," she said.

Tourists had mixed views about a UK "brexit".

Marco Ghiribelli, an Italian tourist, said he thought the UK would be economically better outside.

"It's not economically convenient for the UK to stay in the EU. Brexit makes sense economically as the UK economy is stronger than most of the EU countries."

Others such as Babette Pascalev, a tourist from Germany, said: "I think it is hard now because the idea is to get Europe together not apart."

But others say a Brexit would not make any difference to the tourism business.

They say nothing will change.

Alexander Goransson, travel analyst at Euromonitor International believes the expected drop in sterling following a brexit vote would attract tourists due to an increased spending power.

"In the short term I would expect to see a depreciation of the pound which will have both a positive and negative impact on tourism. UK tourists would be less likely to travel abroad and stay at home, whereas on the other hand the UK would actually become a more attractive destination for inbound tourists as prices would be relatively cheaper."

But most people in the tourist industry are hoping for a remain vote on June 23.

The Houses of Parliament - an iconic London site that attracts visitors from all over the world.

Tourism is now worth 22.1 billion pounds (32 billion US dollars) annually to the UK, according to Visit Britain, Britain's national tourism agency.

Visit Britain also said that last year there were 36.1 million tourist visits, with 67 percent from the European Union.

On 23 June, the UK will vote in a referendum whether to stay in or out of the EU and many in the tourist industry are concerned that a possible leave vote will jeopardise the European holiday market.

One of those is Kyle Haughton, managing director of City Cruises.

His cruise ships carry 6 million passengers a year - in the height of summer 60 percent are from abroad, the majority from the EU.

Of the 240 staff that he employs, 50 percent are from outside the UK, mostly from the EU.

"Any change or decline in passengers coming into the country is going to affect our business quite lot and there are reports that people in Germany, Italy and France are less likely to come to the UK if we leave the EU than if we stay."

His fears are backed up by UK Inbound, which represents 360 tourist businesses.

Deidre Wells, chief executive of UKinbound has called leaving the EU "economic suicide."

"Why would you remove yourself from a market that provides two thirds of our business for our members," she said.

Tourists had mixed views about a UK "brexit".

Marco Ghiribelli, an Italian tourist, said he thought the UK would be economically better outside.

"It's not economically convenient for the UK to stay in the EU. Brexit makes sense economically as the UK economy is stronger than most of the EU countries."

Others such as Babette Pascalev, a tourist from Germany, said: "I think it is hard now because the idea is to get Europe together not apart."

But others say a Brexit would not make any difference to the tourism business.

They say nothing will change.

Alexander Goransson, travel analyst at Euromonitor International believes the expected drop in sterling following a brexit vote would attract tourists due to an increased spending power.

"In the short term I would expect to see a depreciation of the pound which will have both a positive and negative impact on tourism. UK tourists would be less likely to travel abroad and stay at home, whereas on the other hand the UK would actually become a more attractive destination for inbound tourists as prices would be relatively cheaper."

But most people in the tourist industry are hoping for a remain vote on June 23.

London - 2 June 2016

1. Houses of Parliament seen from a river cruise boat

2. Woman taking picture of the Houses of Parliament

3. The London Eye seen from a river cruise boat

4. Part of the London Eye

5. Woman taking photo

6. People on board the river cruise boat

7. St Paul's Cathedral and other buildings

8. River cruise boat approaching Tower Bridge

9. Set up of Kyle Haughton, managing director of City Cruises

10. SOUNDBITE (English) Kyle Haughton, managing director of City Cruises:

"At City Cruises we carry 4 million passengers a year and over half of them come from overseas, the majority of which coming from EU countries, so any change or decline in passengers coming into the country is going to affect our business quite lot and there are reports that people in Germany, Italy and France are less likely to come to the UK if we leave the EU than if we stay."

London - 1 June 2016

11. Various of Deidre Wells, chief executive of UKinbound, at her desk

12. SOUNDBITE (English) Deidre Wells, chief executive of UKinbound:

"I've described it as economic suicide in the past. Why would you deliberately remove yourself from a market that provides two thirds of our business for our members."

London - 2 June 2016

13. People on board the river cruise boat with the Shard in the background

14. Set up of French tourist Kahina Berroua

15. SOUNDBITE (French) Kahina Berroua, French tourist:

"I will be sad. The UK has a lot of power in Europe so it won't be the same."

16. Various of tourists inside the river cruise boat

17. Set up of Marco Ghiribelli, Italian tourist

18. SOUNDBITE (Italian) Marco Ghiribelli, Italian tourist:

"It's not economically convenient for the UK to stay in the EU. Brexit makes sense economically as the UK economy is stronger than most of the EU countries."

19. SOUNDBITE (German) Babette Pascalev, tourist from Germany:

"I think it is hard now because the idea is to get Europe together not apart."

20. Houses of Parliament with open top tourist bus driving past

21. Union Jack flag on top of the Houses of Parliament

22. People on open top bus driving past the Houses of Parliament

23. People on bus

24. People on bus driving past flags

25. Various of Alexander Goransson, travel analyst at Euromonitor International, on laptop

26. SOUNDBITE Alexander Goransson, travel analyst at Euromonitor International:

"In the short term I would expect to see a depreciation of the pound which will have both a positive and negative impact on tourism. UK tourists would be less likely to travel abroad and stay at home, whereas on the other hand the UK would actually become a more attractive destination for inbound tourists as prices would be relatively cheaper."

27. People on open top bus

28. View of London black cabs and Union Jack flags

Tensions mounted in Britain a day before Parliament was due to vote on the Brexit withdrawal agreement, which it has already rejected once.

Ireland's deputy prime minister said Monday that British Prime Minister Theresa May is set to hold last-minute talks with European Union leaders to try to save her foundering Brexit divorce deal.

Simon Coveney said May will fly to Strasbourg, France, a seat of the European Parliament, on Monday "to try to finalize an agreement, if that's possible."

May's 10 Downing St. office would not confirm the trip.

May's office said talks were continuing to try to secure changes to the deal that can win over opponents in Parliament. May has spoken by phone to European Commission President Jean-Claude Juncker twice in the past 24 hours.

Pro-Brexit lawmakers have urged May to postpone Tuesday's vote rather than risk another crushing defeat.

But May's spokesperson said the vote would take place on Tuesday.

London - 11 March 2019

1. Pan from commuters on Waterloo bridge to Westminster skyline.

2. Close up of London Eye

3. Wide of London Eye and Houses of Parliament

4. Boat on river Thames

5. Houses of Parliament with railway bridge in foreground

6. Close up of London Eye with Parliament in the background

7. Pan from Red London buses on Waterloo bridge to London Eye and Parliament in background

8. Commuters on Waterloo Bridge

9. Wide of St Paul's Cathedral and City landscape from Waterloo bridge

10. St Paul's Cathedral and Millennium bridge from across the river Thames

11. Londoners walking across the Millennium bridge

12. St Paul's in background as people cross the bridge

13. Close up of the cross on top of St. Paul's Cathedral

14. Wide of Millennium bridge and St. Paul's cathedral

15. Puddle with reflection of St Paul's Cathedral

16. Wide of St Paul's Cathedral with London buses driving past

17. People looking at Tower Bridge

18. Wide of Tower Bridge

19. London bus driving across the bridge

20. Pan down of Tower Bridge

21. Tourist taking photo

22. Tower of London across the river

23. Wide of tourists walking in front of the Tower of London

24. Close up of Tower of London

25. Pan with tourists walking in front of Buckingham Palace

26. Close up of Union Jack flying above Buckingham Palace

27. Wide of Buckingham Palace

28. Close up the top of the Queen Victoria Memorial

29. Pan of Buckingham Palace

30. Tourist taking photo

31. Wide of Buckingham Palace

32. Close up of window at palace

33. Armed police at the gate of the palace

34. Buckingham palace shot from the Mall

35. Pan of people walking across Lambeth bridge to the Houses of Parliament

36. Mid of flag flying above Houses of Parliament

37. Wide of Parliament through Lambeth bridge

38. Wide of cloudy sky with Parliament and the London Eye

39. Mid of Parliament

40. Parliament with river in foreground

41. Close up of the Union Jack

42. Wide of Parliament

43. People sitting on benches in Victoria gardens in front of Parliament

44. Wide of Parliament

45. Close up of pigeons in front of Parliament

46. Close up of Parliament

47. Wide of Parliament

48. Union Jack on top of Parliament