The United States State Department denied Friday that it had put a deadline on talks with Iran. Earlier in the week it was reported that the U.S. had decided to give dialog a chance until October, but would then turn to tougher sanctions if Iran refused to comply with international investigators.

"We're not interested in setting any deadline. And we're not interested in setting any kind of specific or even notional time-line,” said State Department spokesman Ian Kelly.

"We're not going to let this string out forever, of course,” he added.

The Obama administration has decided that isolating Iran “didn't work,” Kelly said. Instead, the U.S. will hold dialog with Iranian leaders in an attempt to convince the country to open its nuclear program to international investigators, without resorting to further sanctions.

However, the administration has also warned of “crippling” sanctions if dialog fails.

Israel has expressed concern that unlimited dialog with Iran could allow Iran's government to avoid sanctions while actively pursuing nuclear weapons. Earlier this month, Foreign Minister Avigdor Lieberman called on the international community to set a three-month limit on attempts at dialog.

Prime Minister Binyamin Netanyahu will leave for the U.S. on Saturday night, and will meet with U.S. President Barack Obama on Monday. The two leaders are expected to discuss the Iranian threat.

According to Channel 10 news, Netanyahu has expressed concern that the U.S. and Europe will agree to a situation in which Iran stops its nuclear program “on the threshold,” leaving it with the ability to create a nuclear weapon in a short period of time if the political situation were to change.