LONDON (AFP) - Cheering and jeering mingled in the air as Margaret Thatcher's coffin passed through London on Wednesday - a stark reminder that Britain is still as deeply divided over the Iron Lady as when she was in power.

Tens of thousands of admirers lined the funeral procession route to pay their respects to the former British premier, applauding as her coffin travelled to St Paul's Cathedral on a horse-drawn gun carriage.

But at one corner, the applause was drowned out by chants of "Maggie, Maggie, Maggie! Scum, scum, scum!" as around 200 people turned their backs on the passing cortege in an angry protest.

Ill-wishers were outraged by the decision to grant Mrs Thatcher a full ceremonial funeral requiring a massive security operation - at a cost, according to media estimates, of £10 million (S$18.8 million).

Many shouted "Waste of money! Waste of money!" as they turned away from the coffin.

"We're wasting £10 million on a dead witch," said Raffe, a 22-year-old gardener and handyman who, like other protesters gathered near St Paul's, said it was wrong for taxpayers to fund the funeral at a time of deep spending cuts.

"She was out of power by the time I was born but you can still feel the repercussions of what she did," he told AFP.

"She was stony-cold, emotionless and had no regard for the people she originally came from. She was a working class girl who forgot about her background."

Many of the protesters said the former Conservative leader had wrecked millions of lives with radical free-market reforms during her 1979-90 premiership - the same policies that her supporters admire.

"If only her ideas had died," said one placard waved by a mother who had brought her child to the protest in a pushchair.

But on the other side of the road, British army veterans cheered and threw flowers as the procession went past, proudly displaying their medals on their chests.

"She was an exceptional leader," said Gary Sturge, a veteran of the 1982 Falklands War that Mrs Thatcher fought against Argentina after its forces invaded the islands.

"She let her generals and admirals and air marshals get on with the job," added Mr Sturge, whose Parachute Regiment played a central role in the conflict considered Thatcher's finest moment by many of her admirers.

Black-suited young supporters of Thatcher's Conservative Party took up their positions on the route at 7:00 am, three hours before the coffin passed.

"We're here to mark our respect and regard for the greatest peacetime prime minister the country has ever known," said Oliver Cooper, the 26-year-old chairman-elect of Conservative Future, the party's youth wing.

"She gave a huge amount, not just to this country but to others around the world that she helped liberate from totalitarianism. She stood for freedom and democracy."

Earlier on the route, respectful applause broke out as Mr Thatcher's coffin set off from the Royal Air Force church towards the cathedral, where 2,300 global leaders, celebrities and friends were gathered to bid her farewell.

"It's very unusual to clap at funerals - but she was a very unusual woman," said 74-year-old Michael Allmond, a retired company director who, like many, filmed the passing coffin on his smartphone.

Andrew Moodie, another Falklands veteran, said he wanted to "show respect to a great leader".

"She sorted this country out. She made it great again," he told AFP.

Many of Mrs Thatcher's admirers - who vastly outnumbered the protesters on most of the route - said she had come to power in a country in crisis, with soaring inflation and rocketing unemployment.

They insisted that by the time she left power in 1990, she had transformed the economy and restored Britain's position as a major world power.

"She was strong, she was resolute, and she put her country first above any idea of popularity," said Gloria Martin, a London property developer who had an array of "I Love Maggie" badges pinned to her chest.

"People admired her for that - even if they didn't like Thatcher's policies."