♦ Khamenei rejects Trump  offer of talks on tougher  nuclear deal

♦ Supreme leader also slams  economic mismanagement  by Iranian government

Iran's supreme leader said yesterday there would be neither war nor negotiations with the United States, and that the country's problems were the result of government mismanagement more than renewed sanctions.

Ayatollah Ali Khamenei's comments add to the pressure on President Hassan Rouhani following a collapse in the currency and widespread protests over high prices and corruption.

They also appeared to rule out any hope of fresh talks with Washington, which US President Donald Trump had proposed after walking out of the landmark 2015 nuclear deal and reimposing sanctions.

"Beside sanctions, they are talking about war and negotiations... let me say a few words to the people: THERE WILL BE NO WAR, NOR WILL WE NEGOTIATE WITH THE U.S.," Khamenei said via his official Twitter account in English.

There was also a show of military resolve as Defence Minister Amir Hatami unveiled a next generation short-range ballistic missile and vowed to further boost the country's missile capabilities.

State broadcaster IRIB said the new Fateh Mobin missile had "successfully passed its tests" and could strike targets on land and sea.

Despite renewed sanctions, many Iranians -- including many at the highest levels of the establishment -- see US hostility as only a contributing factor to long-standing problems inside the country.

"Today's livelihood problems do not emerge from outside, they are internal," Khamenei said in another tweet.

"Not that sanctions don't have an impact, but the main factor is how we handle them," he added.

Khamenei mirrored recent criticism of Rouhani's economic management from senior members of the clergy and the Revolutionary Guards -- particularly over the collapse of the rial, which has lost around half its value since April.

A fortnight ago, Guards commander Mohammad Ali Jafari told Rouhani to take "revolutionary actions to control prices and prevent the enormous increase in the price of foreign currency and gold," in an open letter published by the conservative Tasnim news agency.

But Khamenei criticised conservatives who called for Rouhani's resignation, saying they were inadvertently "playing into the hands of the enemy".

"The government must stay in office and powerfully carry out its duties to resolve the problems," he said.