WASHINGTON - The leaders of a congressional inquiry into Russia's efforts to sway the U.S. election are asking the Justice Department to provide information related to President Donald Trump's explosive wiretapping allegation.

In a letter sent Wednesday, Sens. Lindsey Graham of South Carolina and Sheldon Whitehouse of Rhode Island are seeking any warrant applications and court orders that could show the Obama administration tapped Trump's phones during the presidential campaign.

The letter went to Acting Deputy Attorney General Dana Boente and FBI Director James Comey.

Graham, a Republican, and Whitehouse, a Democrat, say Congress "must get to the bottom" of Trump's allegation.

They say they would take very seriously any abuse of wiretapping authority for political reasons. They also say they'd be alarmed if there were a legally authorized wiretap of Trump.