Israel has asked Jordan for permission to bomb Syrian chemical weapons sites twice in the past two months, US magazine the Atlantic has reported.

Israel does not need Jordan’s permission to carry out such an attack, but it is reportedly concerned given that a number of potential targets are not far from Jordan’s border with Syria.

An Israeli official told the Atlantic: “You know the Israelis, sometimes they want to bomb right away. But they were told that from the Jordanian perspective, the time was not right."

Intelligence sources have detected that Syria has been transporting the components of chemical weapons to new locations.

US Secretary of State Hillary Clinton said on Monday that the US will act if chemical weapons are used.

“This is a red line for the United States,” she said. “I'm not going to telegraph in any specifics what we would do in the event of credible evidence that the Assad regime has resorted to using chemical weapons against their own people. But suffice to say we are certainly planning to take action.”

Following intelligence reports indicating that Syria plans to use chemical warfare, the Turkish government has requested missile defence systems from Nato, as it fears that missiles directed by the government at Syrian opposition targets will stray into their territory.