Prime Minister Benjamin Netanyahu has increased pressure on Iran.

He said if world powers refused to set a red line for Iran's nuclear programme, they could not demand Israel hold its fire.

Mr Netanyahu added: "The world tells Israel 'wait, there's still time'. And I say, wait for what? Wait until when?

"Those in the international community who refuse to put red lines before Iran don't have a moral right to place a red light before Israel," .

"If Iran knows there is no red line, if Iran knows there is no deadline, what will it do? Exactly what it's doing. It's continuing towards obtaining nuclear weapons capability" he added.

Mr Netanyahu's use of the word "deadline" at a news conference with Bulgarian government leaders, appeared to be a swipe at US Secretary of State Hillary Clinton.

Mrs Clinton said this week the United States would not set deadlines in any further diplomacy with Iran, drawing an angry response from a senior Israeli government official.

Mr Netanyahu has said Israel and the United States were in talks on setting a "clear red line" for Iran's nuclear programme.

Israel, widely thought to be the Middle East's only atomic power, says a nuclear-armed Iran would be a threat to its existence.

Iran maintains its nuclear work is for peaceful energy purposes only.