Tens of thousands of people are expected at Trafalgar Square

Patrols will be increased around key locations amid on-going fears of a terrorist attack.

Crowds of about 100,000 are expected to gather in Trafalgar Square, Leicester Square and Parliament Square.

More are expected to try to see a fireworks display organised by Mayor Ken Livingstone near the London Eye.

Scotland Yard Assistant Commissioner Bernard Hogan-Howe said: "We would say to people, be alert, be vigilant and take care. If you see anything suspicious tell a police officer.

"We have no specific information which makes us think there is a specific threat but generally there is a high level of alert nationally."

He said there would be 500 more officers on duty than last year "firstly because of the general security alert and secondly we have to anticipate the firework display".

He added that he understood the display would be very short, lasting only a few minutes, and could be seen on television.

London Underground, buses and trams will be free from midnight on New Year's Eve with the Tube running until 0430 GMT on 1 January.