WASHINGTON (Reuters) - A Republican member of the House of Representatives vowed on Wednesday to lead a revolt against President Bush's immigration reform proposals and predicted that up to 180 party members would support him.

Bush in an interview with the Washington Times published on Wednesday said he plans to force a debate in Congress this year on his proposal that would allow some illegal immigrants to obtain legal work permits in the United States.

Colorado Rep. Tom Tancredo, who heads the House Immigration Reform Caucus, said he was determined to block the legislation. The caucus, which had 71 members in the last Congress, argues for stronger action to stop illegal immigration and a reduction of legal migration.

"Why is this so important to the president?" Tancredo said. "Is it just the corporate interests who benefit from cheap labor? Do they have such a strong grip on our president so that he is actually willing to put our nation at risk, because open borders do put our nation at risk?

"Is it petulance, because we were able to stop it in the last Congress? Why is it so important to give amnesty to people who have broken the law?" Tancredo said.

"I'm willing to lead a fight against this and I would say there are at least 180 members of our Republican caucus who are willing at least to stop amnesty for illegal immigrants," he told Reuters in a telephone interview...

Bush insists he is not offering amnesty to illegal immigrants but Tancredo said that was a "manipulation of language, the kind of thing (former President) Bill Clinton would have done. There is an issue of integrity here and an issue of honesty," he said.