TEHRAN, Aug. 1 (Xinhua) -- Iranian Foreign Minister Seyed Abbas Araghchi has warned Britain against any military cooperation with the United States in carrying out strikes on Iran.

Iran's Foreign Minister Seyed Abbas Araghchi attends a joint press conference in Tehran, Iran, Jan. 18, 2026. (Photo: Xinhua)

Araghchi made the remarks during a phone call with British Foreign Secretary Ed Miliband on Friday, stressing that any cooperation with "aggressors," including under the pretext of existing defense agreements, would be "unacceptable," according to a statement issued by the Iranian Foreign Ministry on Saturday.

Araghchi criticized what he described as the British government's "unjustified and inappropriate" policies toward Iran, citing London's recent designation of Iran's Islamic Revolution Guard Corps as a national security threat and its "complicity" in two wars imposed by the United States and Israel against Iran in recent months. He called on Britain to reconsider its approach toward Tehran.

He said that under international law and the Convention for the Definition of Aggression, allowing a country's territory and facilities to be used for illegal attacks against another state constitutes an act of aggression and gives the attacked country the right to self-defense.

Araghchi said Iran had entered a diplomatic process with the United States in good faith and signed a memorandum of understanding with Washington in June aimed at ending the conflict, but Washington failed to honor its commitments.

He also highlighted Iran's efforts to establish operational mechanisms with Oman to manage shipping traffic in the Strait of Hormuz, warning that third-party interference would only further complicate matters.

For his part, Miliband said his country was not involved in the war against Iran and maintained that diplomacy was the way to resolve disputes.

Last month, British Prime Minister Andy Burnham approved the continued U.S. use of British military bases for operations related to Iran, maintaining a policy established by his predecessor.

On Feb. 28, the United States and Israel launched joint attacks on Tehran and other Iranian cities, killing Iran's then-Supreme Leader Ali Khamenei, senior military commanders and civilians. Iran responded with waves of missile and drone attacks on U.S. and Israeli bases and assets in the region, while tightening control over the Strait of Hormuz.