Israeli Prime Minister Benjamin Netanyahu said on Sunday Iran's nuclear programme was moving forward rapidly and would be the main focus of his upcoming talks with US President Barack Obama in Washington.

Addressing his cabinet in public remarks, Netanyahu, who meets Obama on 5 March, made no mention of steps Israel might seek or take to try to halt what it says is an Iranian drive to build nuclear weapons.

Recent statements by Israeli officials that time is running out for sanctions to curb Tehran's atomic ambitions have raised US concern Israel could launch pre-emptive strikes on Iran's nuclear sites.

"Undoubtedly one topic will be at the centre of our discussions, and that is, certainly, the continuing strengthening of Iran's nuclear programme," Netanyahu said, referring to his meeting with Obama and talks in Canada several days earlier with Prime Minister Stephen Harper.

Netanyahu said a report by the UN International Atomic Energy Agency on Friday that showed Iran had sharply increased its uranium enrichment drive provided "additional, unequivocal proof ... that Israel's assessments were correct."

Echoing a statement issued by his office on Saturday, the Israeli leader said Iran's nuclear programme was moving forward "rapidly and unchecked" in "defiant and blatant disregard of decisions taken by the international community."

Iran says its is enriching uranium only as fuel for nuclear power plants, not to build weapons.

Israel is widely suspecting of having nuclear weapons, although it publicly denies this.