A group of nearly 200 retired generals and admirals will send a letter to Congress Wednesday urging lawmakers to reject the Iran nuclear agreement, which they say threatens national security.

The letter is the latest in a blizzard of missives petitioning Congress to either support or oppose the agreement with Iran, which lifts sanctions if Iran pares back its nuclear program. Letters have been sent by ad hoc groupings of rabbis, nuclear scientists, arms control and nonproliferation experts — and now, retired senior military officers, many of whom have worked in the White House during various administrations dating back to the 1980s.

The letter, addressed to Republican and Democratic leaders in the Senate and the House, is a response to one sent last week by three dozen retired senior military officers who support the nuclear deal.

“The agreement will enable Iran to become far more dangerous, render the Mideast still more unstable and introduce new threats to American interests as well as our allies,” the letter states.