The United States will use "all elements of American power" to stop Iran from developing a nuclear weapon, US Secretary of State Hillary Clinton said late on Monday at a press conference in Jerusalem.

"We will use all elements of American power to prevent Iran obtaining a nuclear weapon," she said in reference to Tehran's disputed nuclear programme, which Washington and much of the West believes is a cover for a weapons drive.

Her remarks, which carried an implied threat of military action -- a course of action never ruled out by Washington -- came just days after the United States imposed a wave of fresh sanctions on Iran targeting companies tied to Tehran's procurement, petroleum, and shipping networks.

And she accused the Islamic Republic of presenting unworkable proposals in its talks with the P5+1 world powers.

"I made very clear that the proposals we have seen thus far from Iran within the P5+1 negotiations are non-starters," she said of the latest round of talks, which took place in Istanbul earlier this month.

"Despite three rounds of talks it appears that Iran has yet to make the strategic decision to address the international community's concerns and fulfil its obligations."

Following a day of top-level talks with the Israeli leadership over a range of regional issues, Clinton said the Obama administration was "in close consultation with Israel" over ways to increase the pressure on Tehran.

"We talked about concrete steps that we can take to continue to build the pressure," she said.

"We are pressing forward in close consultation with Israel.... And I think it is fair to say we are on the same page at this moment, trying to figure our way forward to have the maximum impact on effecting the decisions that Iran makes."

Because of US efforts to rally the international community to tackle the Iranian nuclear threat, Tehran was "under greater pressure than ever before. That pressure will continue and increase," she said.

"We all prefer a diplomatic resolution and Iran's leaders have the opportunity to make the right decision. The choice is ultimately Iran's," she added.