Live updates: Follow the latest news on Israel-Gaza
British Foreign Secretary James Cleverly has urged Iran to use its influence with groups in the Middle East to prevent an escalation of Israel's conflict with Hamas.
In a call with Iran's Foreign Minister, Hossein Amirabdollahian, Mr Cleverly also said Iranian-backed threats against people in the UK were unacceptable and must stop.
Britain's intelligence services have said there have been at least 15 Iran-backed threats against UK citizens.
It comes as officials have identified a number of UK-based groups with direct ties to Iran.
“The Foreign Secretary spoke to Iranian Foreign Minister Hossein Amirabdollahian,” a Foreign, Commonwealth and Development Office representative said.
“The Foreign Secretary made clear that Iran must use its influence with groups in the region to prevent escalation. He said that Iran bore responsibility for the actions of groups they had supported over many years.
“The Foreign Secretary also reiterated that Iranian-backed threats against people in the UK were unacceptable and must stop.”
However, Mr Amirabdollahian blamed the US for any escalation of the conflict and said Iran does not control militant groups in Palestine, Lebanon, Iraq, Syria or Yemen.
“In continuation of diplomatic consultations, I spoke today with the British Foreign Secretary @JamesCleverly about developments in Palestine and bilateral issues,” he wrote on X, formerly known as Twitter.
“I believe though the United States cannot guarantee Zionists' victory, it can be held responsible for spreading [the] flames of a war.”
The Iranian Foreign Ministry said Mr Cleverly was urged to adopt a “realistic” approach to the conflict.
“In a telephone conversation with his British counterpart, Iran’s Foreign Minister Hossein Amirabdollahian advised London to view the regional developments realistically,” the ministry said on Saturday.
“They discussed the developments in Gaza and some bilateral issues as well. The Iranian Foreign Minister said in any approach to the issue, the Israeli occupation must be viewed as the root-cause of the Palestine crisis.
“Mr Amirabdollahian added that from the perspective of international law, people of an occupied country have a legitimate right to defend themselves. He further made it clear that under international law, the principle of proportionality should also be taken into account in every war.
“In that vein, he noted, the massacre of more than 9,000 Palestinian civilians, in an act of revenge and genocide openly declared by the Zionist regime, is not acceptable by any metric.
“In response to the British Foreign Secretary’s support for the Israeli regime, he recommended that London should look at regional developments in a realistic manner, adding that the Islamic Republic of Iran has always recognised the right to fight occupation based on the principles of international law.
“He underlined that the Israeli regime's genocide in Gaza must be stopped immediately and humanitarian aid should be provided to Gaza in large quantities.
“He said the extensive support provided by the US government to Tel Aviv is to blame for the escalation of the war in the region. He said the resistance forces in the region do not take orders from Iran, but they make decisions based on their own considerations and on the conditions as well as in line with their country's national and regional security.”
Militias supported by Iran have attacked US forces across the region in recent weeks as the war rages on.
Assaults by Iran-backed militias in Syria and Iraq, and Houthis in Yemen, have taken place in relative unison with Israel's continued bombardment of Gaza.