Benjamin Netanyahu is seeking to trap the west into a total war across the Middle East that would have incalculable consequences for the region and the world, Iran’s top diplomat in the UK has claimed, in his first interview since Tehran launched an unprecedented missile and drone attack against Israel at the weekend. Seyed Mehdi Hosseini Matin also warned that if Israel made “another mistake” by launching an attack on Iran, there would be a response from Iran that was stronger, more severe, and administered without a warning like that issued before the weekend attack. The salvo of more than 300 drones and missiles – almost all of which were intercepted by Israel and its allies or fell short of their targets – came in retaliation for a 1 April airstrike on the Iranian consulate in Damascus, Syria, that killed several Iranian Islamic Revolutionary Guards officers. Israel’s top general, Lt Gen Herzi Halevi, has said the country would respond, but it remains unclear what form that would take. “The response to the next mistake of the Zionist will not take 12 days’ time. It will be decided as soon as we see what the hostile regime has done. It will be immediate, and without warning. It will be stronger and more severe,” said Matin, Iran’s chargé d’affaires in London. He ruled out Iran attacking civilian centres or building a nuclear weapon, even though he said Iran knew Israel was an undeclared nuclear state. Both the US and EU have signalled further sanctions against Iran over its attack on Israel, while western leaders have also urged Israel to exercise restraint against escalation. The UK prime minister, Rishi Sunak, said it was a “moment for calm heads to prevail” in a call with Netanyahu, Israel’s prime minister, on Tuesday. Matin, who has been Iran’s senior diplomat in the UK since February 2022 when the ambassador was recalled, denied that Iran had made a strategic mistake by attacking Israel’s military bases, so shifting attention from Gaza to the wider regional conflict in which Iran’s long-term role came into question. Matin argued that the west was losing credibility in the Middle East in a way that would ultimately lead to the US leaving the region, and a peace being reached by regional powers alone. “This is a good opportunity for western countries to demonstrate that they are rational actors, and they are not going to be entrapped by Netanyahu and his goal, which is to be in power for as long as he could actually stay in power,” he claimed. “Iran has considered its actions very carefully, and understood that there is a trap, but not for Iran, for the western countries and allied countries in which they are drawn by the Zionist state into a total war inside the Middle East, and the whole world soon may be unable to control the consequences.” Matin insisted that before the attack on Israel, Iran had urged western officials – including the British foreign secretary, David Cameron – to back a UN security council statement condemning Israel for attacking the Iranian consulate in Damascus. It had also urged the west to back an immediate ceasefire in Gaza, he said. Matin said Cameron had last week refused the Iranian request, even though this week he had admitted that the UK would have responded very strongly if a hostile power flattened a British consulate. “As Cameron mentioned, rightly, every nation has the right to defend itself against this kind of flagrant breach of diplomatic and international law.” He also denied Cameron’s claims that there could have been thousands of civilian casualties if the mass attack of Iranian drones and missiles, which decisively moved its years-long shadow war with Israel into the open, had penetrated the defence of Israel and its allies. He said he found such an accusation extraordinary coming from a government that had armed a regime that had killed 34,000 Palestinians. “Iranian forces didn’t target any populated sites so as to prevent human casualties, nor did it attack government buildings and centres. It was a legitimate defence operation that was conducted in a way that gave considerable warning,” he said. “Now, I can say that the mission is accomplished. And that’s it. That’s what we have announced very publicly, that that mission is concluded.” Matin portrayed the attack as a show of force – “displaying military capabilities, missiles, and drones more powerful than what all the international community expected from Iran” – as he claimed it had been necessary to demonstrate deterrence so no other country would dare to take action threatening its security. “Nobody can, at the moment, imagine that Iran is Iran of the Iran-Iraq war. Iran is now a regional superpower,” he said. He also insisted that Iran had withstood sanctions before, and if the west imposed further sanctions, it would not change course, as since the beginning of the revolution in 1979 Iran had resolved to act independently. Asked about the condemnation of Iran in the British parliament, he said the call to proscribe the Islamic Revolutionary Guards Corps was coming only from rightwing Conservatives, but if ever enforced would lead to reprisals, since the IRGC was part of the Iranian state. “We think that it is better to hear the voice of the British people during the last six months demanding a ceasefire and ending the killing of innocent Palestinian people in Gaza,” he said.