Huge crowds of demonstrators kicked off the march along the banks of the river Thames in the British capital to oppose spending cuts introduced by the Conservative-Liberal Democrat coalition to tackle a record deficit.

Trade unions have said more than 100,000 demonstrators are expected to attend, but Len McCluskey, head of the Unite union, predicted the march would exceed expectations.
“Turnout is past our wildest dreams,” he told AFP, adding that it could be “the biggest protest that the union movement has seen in London in a generation.”

Pubic sector workers, pensioners and students were out on the streets for Saturday’s “March for the Alternative”, brandishing banners reading “Don’t Break Britain”, “No to Cuts” and “Defend Our Public Services”.

Many families with children were among the protesters and the air was filled with the distinctive low-pitched bellow of the vuvuzela, the plastic trumpet whose droning provided the soundtrack for the football World Cup in South Africa.

Steel bands, choirs and dancers also joined the march, giving a carnival atmosphere to the mass demonstration.

Scotland Yard has deployed around 4,500 officers, mindful of several huge student protests against plans to triple university tuition fees that turned violent late last year.

Saturday’s march was to pass the Houses of Parliament and Prime Minister David Cameron’s Downing Street residence before ending in a rally in Hyde Park to be addressed by opposition Labour party leader Ed Miliband.

After coming to power in May, the coalition announced cuts worth £81 billion over five years in order to slash a record public deficit it blames on the previous Labour government.

Dave Prentis, head of the public sector union Unison, hailed the turnout which he said was “absolutely enormous and showed the anger of ordinary working people at the government’s cuts”.

Speaking before the march set off, Education Minister Michael Gove insisted that the protests would not force a change in government strategy.