Revellers across the globe rang in the New Year with fireworks and festivities under tight security after a narrowly-averted Christmas Day airline bomb plot in the United States.

Partygoers from Tuvalu to Tijuana raised a glass to bid farewell to 2009 and usher in a new decade, closing the door on 10 years scarred by wars, terror attacks, natural disasters and financial turmoil.

Paris's Eiffel Tower transformed into a multicoloured light show while in Berlin, more than one million revellers turned up on the boulevard leading to the Brandenburg Gate, the symbol of German unity.

Celebrations in Britain centred on the London Eye, the giant wheel across the river Thames from the Houses of Parliament and Big Ben, as the world's most famous clock heralded the start of the New Year.

A downpour of confetti marked the moment at New York's traditional mass celebration in Times Square in the heart of of Manhattan.

Heavy security was deployed in most cities after a failed Christmas Day bombing of a U.S. passenger jet claimed by Al-Qaida rekindled fears of further attacks.

As huge crowds watched the traditional crystal ball marking the final countdown to 2010, undercover police, surveillance cameras, uniformed teams and radiation and biological detection equipment monitored them.

No backpacks or alcohol were allowed in the  Times Square. “It will be a full fledged deployment of resources,” city police Commissioner Raymond Kelly said. “We assume here that New York is the number one terrorist target in America.”

Highlighting security jitters, the square was briefly evacuated on Wednesday after police discovered what they said was a suspicious vehicle.

A police spokesman said the false alarm was caused by someone who “simply parked illegally in the wrong place at the wrong time of year”.

As the clock ticked past midnight in Sydney, about 4,500 kg of fireworks blasted into the night sky, including one of a giant lollipop and another of the stars of the Southern Cross constellation.

As thousands of people began gathering for the celebrations, police minister Michael Daley urged revellers to keep a lid on their drinking.

Around half a million revellers were expected to crowd Hong Kong's harbourfront to watch 9,000 fireworks set off from the tops of 10 city skyscrapers in a formation resembling a dragon.

But in Thailand, police have banned fireworks and pyrotechnic displays after a New Year's Eve blaze at a Bangkok nightclub a year ago killed 65 revellers.

Multiple bomb blasts in the Thai capital on New Year's Eve 2006 killed three people and left 42 injured, and this year there was expected to be a heavy police presence across the city with bomb disposal teams on standby.

One place where security was to be less of a concern was in Indian Kashmir, thanks to a drop in militant attacks, and locals were set to enjoy some of the first major New Year celebrations in the Himalayan region in two decades.

The Indian resort state of Goa has seen a massive influx of domestic and foreign tourists after a ban on its famed beach parties imposed after last year's militant attacks on Mumbai was lifted.

Indonesia was on high alert after July suicide bombings in two top Jakarta hotels, with police on guard to protect churches and shopping malls.

Security was already tight in Afghanistan and Pakistan after a year of bloodshed for both countries, which are fighting growing insurgencies from Al-Qaeda and Taliban-linked militants.

For international troops in Afghanistan, it was to be business as usual, with soldiers maintaining their normal schedule of operations.