Tehran, Sept 3 (ZEENEWS.COM) UN Secretary General Kofi Annan began a visit to Iran on Saturday as the country's hardline President vowed to pursue its controversial nuclear program, which the west fears is aimed at developing atomic weapons.

The visit comes two days after Iran failed to meet a UN deadline for suspending its enrichment of uranium, paving the way to possible sanctions against the Islamic republic.

Annan flew into Tehran around midday local time today, said Abkar Ghasemi, a Foreign Ministry spokesman.

The nuclear dispute was to top the agenda for the UN chief's two-day meetings, but Annan is also expected to press Tehran to assist in implementation of the UN-sponsored ceasefire in Lebanon, whose Hezbollah guerrillas are believed to receive major financing and weapons from Iran.

The official IRNA news agency said Iran's nuclear programme and the Lebanon situation will dominate Annan's talks.

Annan, who is on a tour of the crisis-wracked middle east, is expected to seek Tehran's support for the UN resolution that halted Israeli-Hezbollah fighting on August 14 and that also called for a beefed-up UN force of 15,000 troops to deploy in the south to enforce the peace.

In Tehran, Annan will meet top officials including President Mahmoud Ahmadinejad, Iran's top nuclear negotiator Ali Larijani and Foreign Minister Manouchehr Mottaki. The exact timing of the meetings was not known but state radio said that the UN chief would hold talks with the Iranian President tomorrow morning.