WASHINGTON, May 26: US lawmakers are urging the Bush administration to topple the government in Iran through covert action.

Speaking on television talk shows over the three-day weekend, which ends on Monday, the lawmakers said they believed US intelligence reports that Iran was harbouring Al Qaeda operatives.

Iran, however, has rejected these allegations as baseless and on Monday a government spokesman in Tehran said they have arrested several Al Qaeda suspects.

Senator Joseph Lieberman, a Democratic presidential hopeful, told Fox News that “a regime change in Iran” would help reduce tensions in the Middle East.”

Senator Pat Roberts, the Republican chairman of the Senate intelligence panel, urged the US government to send “a strong signal” to Tehran that it was supporting “a regime change in Iran.”

“This would bring better cooperation from Tehran,” Senator Roberts told NBC News.

Top Democrat on the Senate Foreign Relations Committee Sen Joseph Biden, however, thought it would not be easy to topple the government in Tehran through covert action.

“I think it’s fanciful,” Senator Biden told NBC’s “Meet the Press. He said he worried that the United States was taking on too much at once, citing the situation in Iraq and Afghanistan. “I’d like to see US finish one job at a time,” he said.