The decision means that international inspectors will not be able to oversee sites, as experts warn that Tehran could revive plans to build a bomb.

Oil futures edged up on Wednesday as Iran suspended cooperation with the U.N. nuclear watchdog and markets weighed expectations of more supply from major producers next month, while the U.S. dollar softened further.

Iranian President Masoud Pezeshkian has approved a law to halt cooperation with the International Atomic Energy Agency (IAEA), a move which will likely obscure any attempt by Tehran to restart its damaged nuclear program.