Irans Supreme Leader yesterday rejected a renewed offer of dialogue with Washington from President Obama, and accused the US of continuing to plot against Tehran while offering peace. Ayatollah Ali Khamenei accused Mr Obama of arrogance for using a Persian new year message to repeat his offer of talks intended to defuse mounting international concern that Iran is building a nuclear bomb. You cannot talk about peace and friendship, and at the same time plot and plan sedition, and think that you can hurt the regime of the Islamic Republic of Iran, said Ayatollah Khamenei in an address on state television to mark Nowruz, the Persian new year. On Saturday Mr Obama sent a message saying that Washington would maintain its commitment to a more hopeful future for the Iranian people, despite US efforts to impose a tougher regime of UN-backed sanctions on Tehran after its refusal to halt uranium enrichment. Our offer of comprehensive diplomatic contacts and dialogue stands. Indeed, over the course of the last year, it is the Iranian Government that has chosen to isolate itself, and to choose a self-defeating focus on the past over a commitment to build a better future, he said. In February, Mr Obama accused Tehran directly of seeking to build a bomb, as Irans nuclear scientists began enriching uranium closer to weapons strength. Inspectors from the International Atomic Energy Agency were called to the plant at Natanz to witness work that will upgrade Irans 3.5 per cent enriched uranium to 20 per cent. From here, experts say the step up to weapons-grade could be made within months. Several EU countries , including Britain, are said to be close to agreeing targeted sanctions on Iran for jamming satellite television services and imposing internet censorship. Britain and France have led a push to make a formal protest after Monday's meeting of the 27 EU foreign ministers in Brussels. A draft of the foreign ministers' statement seen by The Times states: "The EU expresses its grave concern over measures taken by the Iranian authorities to prevent its citizens from freely communicating and receiving information through TV, radio satellite broadcasting and the internet. "The EU calls on the Iranian authorities to stop the jamming of satellite broadcasting and internet censorship and to put an end to this electronic interference immediately. The EU is determined to pursue these issues and to act with a view to put an end to this unacceptable situation."(The Times)