Israel has warned that it will not hesitate to act alone against Iran, based on the findings of a recent report, which says that Iran has the capability to produce sufficient weapons-grade uranium to build a nuclear bomb in less than a month. Israeli government said, the report issued Thursday by the Institute for Science and International Security (ISIS) is further justification why Israel will initiate military action before Iran can build its nuclear bomb. The Obama administration, meanwhile, has approached Congress to put-off new sanctions against Iran, as talks progress.

"We have made it crystal clear - in all possible forums, that Israel will not stand by and watch Iran develop weaponry that will put us, the entire Middle East and eventually the world, under an Iranian umbrella of terror," Danny Danon, Israel's deputy defence minister was reported to have told USA Today.

The United States and other world powers fear Iran is trying to develop nuclear weapons. Iran, meanwhile, has been saying its program is for peaceful energy production.

This week's meeting between the world powers and Iran is focused on how to scale back Iran's enrichment of material that can be used to generate power or nuclear warhead material.

The Israeli warning comes even as; the Obama administration has approached Congress to put-off new sanctions against Iran. The U.S. feels that, hold on new penalties will provide negotiators flexibility for productive talks with Iran, currently underway.

A pause in new sanctions will be "helpful in terms of providing some flexibility while we see if these negotiations will move forward," said State Department spokeswoman Jen Psaki.

It is a consensus decision of the administration's national security teams, she pointed out.

"We have conveyed that any congressional action should be aligned with our negotiating strategy as we move forward. So while we understand that Congress may consider new sanctions, we think this is a time for a pause, as we asked for in the past, to see if negotiations can gain traction," Psaki told reporters.

Additional sanctions can be imposed later if the Iranians fail to meet their obligations, she stressed.

No existing sanctions, however, are being lifted, she said.

Israel and several U.S. lawmakers, however, argue that not easing pressure and imposing new sanctions will give the Obama administration further leverage during the talks with Iran.