Iran said on Wednesday it would present "new proposals" regarding its nuclear program at talks with six world powers that will open in Istanbul over the weekend. Said Jalili, Tehran's chief nuclear negotiator, told the Iranian media he hopes his interlocutors - the United States, Britain, China, Russia and France - "enter the talks with constructive approaches."

Jalili didn't go into details, but he was more conciliatory compared with Tehran's statements earlier this week, which dismissed the United States' proposed overtures that were published by the New York Times. Foreign Minister Ali Akbar Salehi, for example, warned against setting preconditions for the talks, saying they would not help resolve the crisis.

The talks, which will start on Saturday, are the first negotiations between the parties to the forum since the last round was suspended in January last year. They have already agreed that the next round will take place in Baghdad, at a time that has yet to be determined.

Israeli officials have said that the U.S. administration is putting more pressure on Iran than before; this is due to Israel's threats to strike Iran's nuclear facilities over the past few months. Ministers have said the current international sanctions go beyond what Israel thought would be possible at this stage.

Paralyzing international trade

The escalating pressure includes cutting off Iranian banks from a system facilitating international transfers - effectively paralyzing Iran's international trade.

It also includes the mounting U.S. military presence in the Persian Gulf, which poses a real threat to the Islamic Republic. In an apparent move to strengthen its position ahead of the talks, Iran lashed back this week and halted oil exports to Germany, Spain and Greece.

But both Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak have said that the current sanctions - though rigorous - won't be enough to halt the Iranian nuclear program. U.S. officials have been saying that a containment policy is no longer relevant, which President Barack Obama stressed in his speech to AIPAC last month.

Obama's more assertive stance on Iran cannot be solely attributed to Israel's belligerent rhetoric, which the White House is bending over backward to rein in. It also has to do with domestic politics, after a series of debates between the Republican presidential hopefuls that has put Iran at the top of the country's foreign affairs agenda.

When the Republican candidates compete with one another on scaring Iran, the president has to step up the rhetoric, too. He understands that if a nuclear Iran comes into being, it will be forever remembered as the failure of his administration, on his watch.