Saeed Jalili, who heads Iran's Supreme National Security Council, is holding talks today in London with EU foreign policy chief Javier Solana prior to a meeting in Paris on December 1 between the six countries mediating in the Iranian nuclear dispute.
"This visit is possible, but will depend on the outcome of the talks between the six nuclear mediators," the source said.
On December 1, the Iran Six will discuss new tougher sanctions against the Islamic state, which has repeatedly ruled out any possibility of acquiescing to a UN Security Council demand that it halt uranium enrichment.
At the Paris meeting on Saturday, the UN Security Council members - the United States, Russia, Britain, France, China, and Germany - will also review the report delivered earlier this month by the chief of the International Atomic Energy Agency (IAEA), Mohamed ElBaradei.
The document stresses the positive aspects of Iran's "nuclear dossier," saying the country has provided extra documentation, but notes that it is continuing to enrich uranium.
Iran has interpreted this as IAEA recognition of its nuclear program's stated peaceful goals, and has demanded that sanctions against it be lifted.
Tehran insists it needs nuclear technology to generate electricity. However, the U.S. and other states suspect that Iran's research is aimed at the creation of nuclear weapons.
Iranian President Mahmoud Ahmadinejad has said his country's efforts to withstand Western pressure to close down the nuclear program are of more importance to him than the actual program itself, saying on November 21 that the country would gain "a greatness that is 100 times more precious than nuclear energy," if it were able to do so.
"Confronting those who speak in the language of aggression... is more important than the possession of know-how in the nuclear sphere," he said at a rally at Ardebil, a city in the northeast of Iran.