Protesters chant anti-U.S. slogans during a demonstration against the killing of Iranian Revolutionary Guard Gen. Qassem Soleimani, close to United States' consulate in Istanbul, Sunday, Jan. 5, 2020. Picture: Lefteris Pitarakis/AP

Protesters chant anti-U.S. slogans during a demonstration against the killing of Iranian Revolutionary Guard Gen. Qassem Soleimani, close to United States’ consulate in Istanbul, Sunday, Jan. 5, 2020. Picture: Lefteris Pitarakis/AP

A supporter of Hezbollah leader Sayyed Hassan Nasrallah wears the words "powerful revenge" on her hand, ahead of the leader's televised speech in a southern suburb of Beirut, Lebanon, Sunday, Jan. 5, 2020 following the U.S. airstrike in Iraq that killed Iranian Revolutionary Guard Gen. Qassem Soleimani. The placard in her other hand depicts Soleimaini and Iraq's Popular Mobilization forces commander Abu Mahdi al-Muhandis, who was also killed in the strike. Arabic on placard reads: "On the road to Jerusalem." (AP Photo/Maya Alleruzzo)

A supporter of Hezbollah leader Sayyed Hassan Nasrallah wears the words “powerful revenge” on her hand, ahead of the leader’s televised speech in a southern suburb of Beirut, Lebanon, Sunday, Jan. 5, 2020 following the U.S. airstrike in Iraq that killed Iranian Revolutionary Guard Gen. Qassem Soleimani. The placard in her other hand depicts Soleimaini and Iraq’s Popular Mobilization forces commander Abu Mahdi al-Muhandis, who was also killed in the strike. Arabic on placard reads: “On the road to Jerusalem.” (AP Photo/Maya Alleruzzo)

WASHINGTON — President Donald Trump insists that Iranian cultural sites are fair game for the U.S. military, dismissing concerns within his own administration that doing so could constitute a war crime under international law. 

He also warned Iraq that he would levy punishing sanctions if it expelled American troops in retaliation for the killing of one of its top military commanders.

But Congress is pushing back, in what’s expected to be a pivotal week as lawmakers return from a holiday recess. On Monday, two top Senate Democrats called on Trump to immediately declassify the administration’s reasoning for the strike on the Iranian official, Gen. Qassem Soleimani, saying there is “no legitimate justification” for keeping the information from the public.

And House Speaker Nancy Pelosi said late Sunday the House would introduce and vote this week on a war powers resolution to limit the president’s military actions regarding Iran. In a letter to House Democrats, Pelosi called the airstrike “provocative and disproportionate” and said it had “endangered our servicemembers, diplomats and others by risking a serious escalation of tensions with Iran.” A similar resolution was introduced in the Senate.

Congress, which has the sole power to declare war, has complained that Trump did not provide advance notice of his decision to strike in Iraq. Trump did meet the 48-hour deadline required by the War Powers Act to notify Congress after the deadly drone strike, though the document was classified and no public version was released.