US Defence Secretary Chuck Hagel urged caution Wednesday over an Israeli claim Syria's regime used chemical weapons, saying it was "serious business" and any evidence had to be weighed carefully. Warning against a possible rush to judgement, Hagel indicated he had been caught off guard by allegations from an Israeli general this week that Syria had fired chemical agents against rebels in recent months.

US Defence Secretary Chuck Hagel was meeting Israel's Benjamin Netanyahu on Tuesday at the end of a three-day trip which saw him touting strong backing for Israel despite differences over Iran's nuclear project. With US-Israeli relations strained over questions about the imminence of the threat posed by Iran's nuclear programme and Hagel dogged by his past criticisms of Israel, the Pentagon chief has stressed his full-throated support for the Jewish state in his first visit as defence secretary.

Pentagon chief Chuck Hagel met his Israeli counterpart Moshe Yaalon on Monday to put the finishing touches on a major arms deal and for talks on Syria's civil war and the Iranian nuclear threat. Speaking at a joint news conference in Tel Aviv, Hagel confirmed the two had finalised details of a multi-billion dollar arms deal which will see Israel receiving an impressive package of advanced US missiles and aircraft.

A major US arms deal with Israel sends Iran a "very clear signal" that military action remains an option to stop it from going nuclear, US Defence Secretary Chuck Hagel said on Sunday. Hagel's comments came shortly before his arrival in the Jewish state at the start of a six-day regional trip likely to be dominated by worries over Iran's nuclear programme and Syria's civil war.