Secretary of State John Kerry and Defense Secretary Chuck Hagel testified to the Senate Foreign Relations Committee on Tuesday to argue the Obama administration's case for using military force in Syria, NBC News reported.

The hearing brings the formal process for considering and debating President Barack Obama's request for congressional authorization to strike Syria in retaliation for a suspected chemical weapons attack that killed more than a thousand people in the suburbs of Damascus.

Senators are seeking to tweak the resolution that the White House sent to Congress on Saturday.

Tuesday's testimony is part of an all-hands push by the administration to convince a clearly skeptical Congress that punishing Syrian President Bashar Assad's government is the right thing to do.

Already, on Monday, Republican Senators John McCain and Lindsey Graham called on the president to make a stronger case to Congress and the American public.