Iran leader slams 'catastrophic' US election

Iran's supreme leader said Wednesday that the level of debate between the US presidential election frontrunners showed the "catastrophe" of American politics and warned against any further negotiations with Washington.

"These two candidates (Hillary Clinton and Donald Trump) show the catastrophic reality which goes beyond what even we were saying," Ayatollah Ali Khamenei said in a speech reported on his website.

"Their statements are proof of the destruction of human values in the United States," Khamenei said.

Khamenei's speech came as Iran marked the 37th anniversary of the storming of the US embassy in Tehran by radical students, who took more than 50 staff hostage for 444 days sparking a rupture of diplomatic relations that lasts to this day.

He said Iran's continued exclusion from the global banking system despite the lifting of international sanctions under a nuclear deal with world powers showed the United States could not be trusted.

"Some people try to develop this dangerous idea that if we compromise with the United States, the problems of our country will be solved," he said.

"The nuclear deal and the attitude of the United States are an example that shows this is not correct."

Although international sanctions were lifted in January, Washington has maintained its own sanctions related to human rights and Iran's missile programme -- effectively preventing Iran's return to the banking system.

Khamenei, who has the final say in all matters of state in Iran, said he saw no point in holding talks with Washington on the multiple conflicts gripping the region.

"Some say we should negotiate and compromise with the United States with regard to Syria, Hezbollah in Lebanon, Iraq, Afghanistan, Yemen and even our internal affairs.

"Negotiating with the United States will not solve the problems. First, because they lie, they don't respect their commitments, trick others. And secondly, because the United States is itself in crisis."