Dubai: Iran's Supreme Leader Ayatollah Ali Khamenei on Wednesday warned the US against hidden "threats" in the talks over his country's nuclear programme and accused Washington of attempting to impose its will in negotiations with Tehran.

"We do not want any negotiation, the result of which is pre-determined by the United States," he added.

While accusing the US of adopting a "superficial conciliatory tone", Khamenei said Washington's actions are in contradiction to what it says. Khamenei's attack came on the eve of the 30th anniversary of the seizure of US embassy in Tehran.

Meanwhile, Iranian police warned opposition against using Thursday's anti-US rally to revive protests against the establishment.

Opposition leaders have urged their supporters to take to the streets on Thursday.