The lawmakers said the threats could be a precursor to a new attack inside the United States by bin Laden's al-Qaida network.
"When Osama bin Laden says he's going to attack the United States and he's focused on attacking us in the homeland, we should take him very, very seriously," Rep. Pete Hoekstra, R-Mich., told ABC's "This Week."
Hoekstra is chairman of the House Permanent Select Committee on Intelligence. His counterpart on the Senate Select Committee on Intelligence, Sen. Pat Roberts, R-Kan., said he knew of "no specific threat," but he told CBS' "Face the Nation" bin Laden's warning should be taken seriously.
"If you take that line that he said 'We are preparing every minute and every minute and when we're ready we're going to attack you in your homeland,' I think we have to take that very seriously," said Roberts.
Rep. Jane Harman, D-Calif., the ranking member on Hoekstra's committee, said she has called on Homeland Security Secretary Michael Chertoff to consider raising the national color-coded threat level in key cities.