US President Donald Trump has sent Congress a formal notification that hostilities against Iran resumed on July 7, a letter his administration sees as opening a new 60-day window to use the military in the region without congressional approval, Reuters reports.

“I directed this military action consistent with my responsibility to protect Americans and United States’ national security and foreign policy interests,” Trump said in the letter, dated July 10.

The letter outlines Trump’s actions, including ordering a two-week ceasefire on April 7, which was extended, and his administration’s efforts to achieve a diplomatic solution to the conflict.