WASHINGTON — With Israel openly debating whether to strike at Iran’s nuclear facilities in the coming months, the Obama administration is moving ahead with a range of steps short of war that it hopes will forestall an Israeli attack, while forcing the Iranians to take more seriously negotiations that are all but stalemated.

Already planned are naval exercises and new antimissile systems in the Persian Gulf, and a more forceful clamping down on Iranian oil revenue. The administration is also considering new declarations by President Obama about what might bring about American military action, as well as covert activities that have been previously considered and rejected.

Later this month the United States and more than 25 other nations will hold the largest-ever minesweeping exercise in the Persian Gulf, in what military officials say is a demonstration of unity and a defensive step to prevent Iran from attempting to block oil exports through the Strait of Hormuz. In fact, the United States and Iran have each announced what amounted to dueling defensive exercises to be conducted this fall, each intended to dissuade the other from attack.

The administration is also racing to complete, in the next several months, a new radar system in Qatar that would combine with radars already in place in Israel and Turkey to form a broad arc of antimissile coverage, according to military officials. The message to Iran would be that even if it developed a nuclear weapon and mounted it atop its growing fleet of missiles, it could be countered by antimissile systems.