WASHINGTON - A bipartisan group of US lawmakers on Wednesday filed a lawsuit against President Barack Obama over his handling of military operation in Libya without congressional authorization.

Democratic House Representative Dennis Kucinich, together with Republican Representative Walter Jones, led a bipartisan group of anti-war lawmakers in challenging the Obama administration in a federal court.

"With regard to the war in Libya, we believe that the law was violated. We have asked the courts to move to protect the American people from the results of these illegal policies," said Kucinich.

He criticized the Obama administration for "circumvention of Congress and its use of international organizations such as the United Nations and the North Atlantic Treaty Organization to authorize the use of military force abroad."

Obama is under increasing pressure from Congress for his decision to launch military action in Libya without congressional approval. House Speaker John Boehner warned Tuesday that Obama would be in violation of US law if he can not gain congressional authorization for military operation in Libya by this weekend.

The Speaker was referring to the 1973 War Powers Resolution, which requires congressional authorization within 60 days of military action. The law also includes a further 30-day withdrawal period. Boehner said the 90 days expires on Sunday.

Earlier this month, the House adopted a resolution rebuking the Obama administration for launching military operation in Libya without congressional approval.

However, the White House rejected the resolution and insisted the administration has been in regular consultations with Congress and did not violate the law as a result.