Iran’s president has enacted a law to suspend cooperation with the United Nations’ nuclear watchdog, Iranian state media reported on Wednesday, in a move that will shut out international inspectors from overseeing the country’s contested nuclear program.

The new law will further strain relations between Iran and the International Atomic Energy Agency, which were already at a low point since the start of the 12-day war with Israel and the United States.

Experts have warned that Iran could start to secretly work on building a nuclear weapon after its facilities were battered by the Israeli and U.S. strikes. But the move to cut ties with the I.A.E.A. could also be a tactic to gain leverage in new negotiations with the Trump administration over the future of its nuclear program.

Iran has said its nuclear program is for civilian purposes only. The I.A.E.A. has said that it had no evidence that Iran was building a bomb, but that the country was stockpiling 400 kilograms, or 882 pounds, of highly enriched uranium, which could enable the government to build 10 bombs.

It is unclear how badly Iran’s nuclear program was damaged by the U.S. and Israeli strikes. President Trump has insisted it was “obliterated” while Rafael Grossi, the I.A.E.A. director general, has said that Iran could begin enriching uranium again in a “matter of months.”

One of the I.A.E.A.’s main purposes is to monitor the nuclear activity of countries that have signed on to the Nuclear Nonproliferation Treaty and to try to prevent the building of nuclear weapons. Iran is a party to the treaty. Israel, which is widely believed to have nuclear weapons but has never confirmed it, is not.