Iran's Foreign Ministry condemned the new British government's decision to allow the United States to use its military bases and facilities to prepare for and facilitate unlawful military attacks against the Iranian people.

In a statement, the Iranian Foreign Ministry said the decision clearly contradicts the fundamental principles and rules of the UN Charter and international law. It added that the move would constitute an act of aggression against Iran under Article 3(f) of UN General Assembly Resolution 3314 on the definition of aggression.

Iran says UK decision violates international law

The statement said British politicians made the decision while fully aware that US military attacks on Iran, which began with the participation of the Israeli occupation and have continued, constitute explicit aggression and a flagrant violation of the fundamental principles of the UN Charter and peremptory norms of international law.

It added that "any participation or cooperation in preparing for and carrying out these unlawful attacks constitutes complicity in the commission of the crime of aggression and war crimes."

The Iranian Foreign Ministry said the British government, in its national capacity and as a permanent member of the UN Security Council, had chosen to side with the aggressors instead of condemning the military aggression and war crimes allegedly committed by the United States and the Israeli occupation against Iran.

Tehran said Britain's position had effectively made it a partner in a brutal war against the Iranian people, undermining London's claims of supporting the rule of law, human rights, and international peace and security.

Tehran accuses Britain of complicity in aggression

The statement said support from Britain's ruling party for the unlawful US-Israeli war against Iran not only violated international legal obligations to respect Iran's national sovereignty and territorial integrity, but also "recalls the historical atrocities and interventions of the United Kingdom against the Iranian people, which culminated in the 1953 coup, and continued later in the form of comprehensive support for Saddam Hussein's regime during the eight-year imposed war, the imposition of illegal sanctions under the pretext of the nuclear issue, as well as following the United States in the snapback mechanism and the ridiculous designation of the Islamic Revolution Guard Corps."

The Iranian Foreign Ministry concluded by reaffirming the Islamic Republic's determination to defend its national sovereignty, territorial integrity, interests and national security against any foreign aggression. It warned that any party participating in any way in an act of military aggression against Iran would bear responsibility for the consequences of its decision.

Not a UK first

The British government in March authorized the United States to use military bases on UK soil to carry out operations targeting Iranian sites.

A statement from Downing Street, the office of the Prime Minister, said British ministers held a meeting to discuss the latest developments in the war on Iran and the implications of Tehran’s closure of the strategic waterway. The statement emphasized that the agreement with Washington falls under the framework of “collective defense” for the region.

The agreement reportedly includes support for US operations aimed at attacking Iran's missile capabilities, under the pretense that they could be used to sustain the closure of the Hormuz Strait.

Earlier, then-Prime Minister Keir Starmer stressed that the UK would not be drawn into a war with Iran, noting that he initially rejected a similar US request pending verification of the legal framework and legitimacy of any potential military action.