By Brian Wheeler BBC News politics reporter

John Prescott has been attacked by the press for allegedly putting two fingers up at the Conservatives during prime minister's questions in the Commons.

Watch the incident

The deputy prime minister can clearly be seen waving a pair of digits at the baying benches opposite, as Tony Blair answers a question on climate change.

Closer inspection of the tape suggests Mr Prescott may simply have been using his fingers to emphasise a point rather than deliberately making a rude "v-sign".

Or perhaps the veteran Labour minister was employing a classic piece of playground innuendo - making a point and syly sticking two fingers up at the enemy at the same time.

Either way, it is not the first time Mr Prescott has let his fingers do the talking.

In 2001, suspicions were aroused when, during an election rally, he raised first one finger and then another to illustrate how Labour had delivered social justice and economic stability.

Noble lineage?

The lingering v-sign that resulted was written off as innocent mistake.

Mr Prescott lets his fingers do the talking

Two years later Mr Prescott appeared to flash a v-sign at photographers outside Downing Street.

In January this year, he was apparently at it again, snapped with two fingers aloft at a "sustainable communities summit" in Manchester.

Some critics have suggested such behaviour - deliberate or otherwise - brings the office of deputy prime minister into disrepute, but perhaps they are ignoring the noble lineage of the two fingered gesture.

The v-sign, with knuckles facing forward, is a uniquely British symbol of defiance.

Not for Mr Prescott the more fashionable, raised middle finger favoured by the Americans and, thanks to Hollywood, angry motorists, surly teenagers and posturing rock stars the world over.

Winston Churchill

Britons have been sticking two fingers up since the Middle Ages.

A message for the press - no make that two messages

As any saloon bar historian will tell you, the gesture dates back to English archers at Agincourt in 1415, who stuck up two fingers in defiance of the French threat to cut off their fingers if captured.

Winston Churchill was rarely seen in public without two fingers proudly aloft - denoting v for victory.

Mr Churchill normally had his palms facing forward but, according to the Churchill archive, there are also pictures of him giving the v sign the Prescott way.

The v-sign as rude gesture reached a peak of popularity in the 1970s, when show jumper Harvey Smith - like Mr Prescott a bluff northerner adrift in a world of toffs - made it his trademark.

Vulgar abuse

In 1990, the Sun newspaper did its bit for the entente cordiale by urging its readers to stick two fingers up at then President of the European Commission Jacques Delors.

Its "Up Yours, Delors" front page attracted scores of complaints about its alleged racism.

But the now defunct Press Council cleared the newspaper after it said it reserved the right to use vulgar abuse whenever it felt it justified in the interests of the British people.

With Anglo-French relations again at something of a low point, perhaps the real targets of Mr Prescott's two fingered tribute were not sitting on the benches opposite after all...