By Ian Youngs BBC News Online Entertainment staff

Rock band Radiohead have joined thousands of protesters in a mass lobby of parliament to help mobilise "people power" against global trade laws.

Their presence boosted the profile of the event, which was expected to see 10,000 people descend on Westminster.

The group said they would "hopefully" get to meet their local MP - Liberal Democrat Dr Evan Harris, who represents Oxford West - to urge him to sign a House of Commons motion to support the campaign.

Singer Thom Yorke said he was there because trade laws were "completely outmoded and exploitative towards poor countries".

Ultimately it does make a difference - we are the people

Ed O'Brien guitarist

The band were taking a break from preparations for a string of concerts in Spain and Portugal in July and August, at which new material is expected to make its debut.

Mexican wave

The rally was organised by the Trade Justice Movement, a new pressure group comprising charities including Christian Aid, Oxfam and Save the Children.

The band's campaigning follows the high-profile support they gave to the "drop the debt" Jubilee 2000 cause, which has now ended.

"For me personally, it was a real sense of frustration when it ended," Thom Yorke told BBC News Online.

"I find that the Trade Justice Movement, in a way, is bringing back all those issues."

Yorke meets the media

The trade laws are "pretending to be in the interests of the poorest, but are really highly exploitative," he said.

The group were due to take part in a mass "mexican vave" of noise that passed down the line of protestors waiting to meet their MPs that stretched across the Thames.

Guitarist Ed O'Brien said they felt like they could make a difference.

"You meet a lot of people who are similar to you and who feel the same way and ultimately it does make a difference," he said. "We are the people."

He said it was "fantastic" to see so many people of all ages at the rally.

"And it's not just in Britain, it's around the world, and that's really encouraging, that's really exciting," he said.

Fair trade

He had been to May Day anti-globalisation protests in London for the last three years, he said.

It's something that we're well into, and hopefully we don't have the sort of fans who just follow us around like that

Thom Yorke singer

"I feel very strongly about how trade is done throughout the world, how unfair it is, and how it places burdens that can never be removed on developing countries.

"They are complicit in being the main source of poverty and environmental damage to the planet."

The band tries to buy fair trade products as well as raising awareness, he said.

Yorke said he was not tying to send a message to the band's fans - but they could join the crusade if they wanted to.

"It's something that we're well into, and hopefully we don't have the sort of fans who just follow us around like that," he said.

"I don't think we do, actually.

Yorke says he does not expect fans to follow him

"We put addresses on our website, but we do not tell people to go there. It's like, if you're interested, whatever."

He has previously condemned those in charge of free trade rules as "a bunch of lunatic economic zealots waving stupid little flags".

Yorke is one of the highest-profile rock stars to take up charity issues, and has also spoken out in favour of CND and the War on Want.

He sent a Christmas message to his fans, saying President George W Bush had "his hands covered in oil and military hardware" and said the world needed "love, understanding and tolerance and good laws that apply to everyone".

Yorke has said that a new CD will be out "sooner than you think" after they released two albums in 2001.

The first single that will be taken from the new material is rumoured to be called Parrots.