WASHINGTON, Jan 2: US lawmakers urged their government on Sunday to rescind a reported plan to keep dangerous terror suspects in prison without trial for the rest of their lives.

Hours after some US newspaper reported the plan, lawmakers from both the ruling Republican and the opposition Democratic parties appeared on national television channels to condemn the move.

According to the report, the Pentagon and the CIA have asked the White House to decide on a more permanent approach for those it was unwilling to set free or turn over to US or foreign courts. Some of these suspects could be imprisoned for a lifetime, the report said.

"It's a bad idea. So we ought to get over it and we ought to have a very careful, constitutional look at this," Republican Sen. Richard Lugar of Indiana who also heads the Senate Foreign Relations Committee said on "Fox News Sunday."

Sen. Carl Levin of Michigan, senior Democrat on the Armed Services Committee, cited earlier US Supreme Court decisions to show that the move was unconstitutional.

"There must be some modicum, some semblance of due process ... if you're going to detain people, whether it's for life or whether it's for years," Mr. Levin said, also on Fox.

The White House did not immediately respond to requests for comment. The State Department declined comment and a Pentagon spokeswoman she had no information on the reported plan.

As part of a solution, the US Defence Department, which holds 500 prisoners at Guantanamo Bay, plans to ask the US Congress for $25 million to build a 200-bed prison to hold detainees who are unlikely to ever go through a military tribunal for lack of evidence, defence officials told the Washington Post.

The new prison, dubbed Camp 6, would be designed for prisoners the government believes have no more intelligence to share but were too dangerous to set free. "It would be modeled on a US prison and would allow socializing among inmates," the Post said.

"Since global war on terror is a long-term effort, it makes sense for us to be looking at solutions for long-term problems," Bryan Whitman, a Pentagon spokesman, told the Post.

"This has been evolutionary, but we are at a point in time where we have to say, 'How do you deal with them in the long term?" The Post said the outcome of a review under way would also affect those expected to be captured in future counter terrorism operations.

One proposal calls for the transfer of large numbers of Afghan, Saudi and Yemeni detainees from the US military's Guantanamo Bay, Cuba, detention center into new US-built prisons in their home countries.

The prisons would be operated by those countries, but the State Department, where this idea originated, would ask them to abide by recognized human rights standards and would monitor compliance.