Iran has spurned two messages from Donald Trump’s special envoy, Steve Witkoff, seeking a ceasefire as its leaders sense it is not losing the war and the US president is at the minimum feeling the political pressure.

The foreign minister, Abbas Araghchi, has further said a unilateral declaration from Trump that the US had won the war would not bring an end to the conflict. The implication is that even if the US announced a willingness to end its attacks, Iran might be willing to continue the conflict in some form, or keep its chokehold on shipping seeking to navigate the strait of Hormuz.

Iran believes there can be no end to the conflict until it believes Trump has been shown the economic, political and military cost is so high that it is not worth repeating. It is instead insisting on a permanent deal that includes a US commitment not to attack Iran again.

“If a ceasefire is to be established or the war stopped there must be a guarantee that aggressive actions against Iran will not be repeated. Otherwise if another attack occurs after a few months such a ceasefire would be meaningless,” said Kazem Gharibabadi, the deputy foreign minister.

The defiance is remarkable for a regime that at the start of the war 11 days ago was seeking little more than its own survival.

Nevertheless, the foreign ministry in conversations with the large number of countries offering to mediate is exploring whether it is feasible for the war simply to stop as it did in June last year, or must end with some kind of pact that might include a conditional lifting of US economic sanctions.

But the overall mood among Iranian regime figures is that it is going to survive and should not at this stage seek any agreement. It will come under intense diplomatic pressure at the UN security council on Wednesday when more than 80 nations will sponsor a Bahrain-sponsored resolution condemning Iran for its attacks on the Gulf States, but voicing no criticism of the US or Israel. Russia may sponsor a separate motion calling for a ceasefire.

“We are absolutely NOT seeking a ceasefire,” the speaker of the parliament, Mohammed Ghalibaf, posted to social media. “Let the enemy know that whatever they do, there will certainly be a proportionate and immediate retaliation […] We are fighting eye for eye, tooth for tooth, without compromise or exception.”

The Islamic Revolutionary Guards Corps (IRGC) has stressed that it will control the strait of Hormuz, which carries nearly 20% of the world’s crude oil and about 20% of liquefied natural gas. “At the beginning of the war we announced and we announce again no vessel associated with aggressors against Iran has the right to pass through the strait of Hormuz,” it said. “If you have doubts, come closer and find out.” The IRGC has also said it will allow ships though from countries that expel their US and Israeli ambassadors.

Even the less militant president, Masoud Pezeshkian, sounded a defiant note arguing “the destroyers have come and gone. Iran remains.”

Iranian diplomats argue that after two previous rounds of diplomatic talks being cut short by US-Israeli airstrikes, there is simply no basis to reach an agreement.

Trump at his press conference on Monday night was meanwhile rehearsing the various arguments for a declaration of victory, possibly because the US had sufficiently damaged its ballistic missile launchers and nuclear programme that there was no need to continue the attack. But ultimately he refused to assert US victory was complete.

Alex Vatanka, a senior fellow at the Middle East Institute, said: “The regime overall think they can stay in this war and it might actually legitimise them because otherwise they have been a disaster for the country.” He blamed some of Israel’s attacks on energy infrastructure – which sent clouds of black smoke through Tehran – for alienating Iranian opinion.

“Over the course of 24 hours you could sense the shift in Iranian public opinion from a war against regime to a war on Iran,” he said.

Emile Hokayem from the International Institute for Strategic Studies nevertheless pointed to Iran’s significant self-inflicted problems. “The regime is still standing but faced a massive issue of resources,” he said. “Where do the resources come from when you have lost your ability to export when Hormuz is closed because of your own threats when the region does not want to trade with you and the United Arab Emirates is considering to freeze its assets.”