Israel's army on Wednesday staged a surprise drill on the country's northern border, the military said, amid tensions over Iran's nuclear drive and the fate of Syria's chemical weapons.

The one-day exercise was ordered by army chief Lieutenant General Benny Gantz, a military statement said, "in order to examine the competence and preparedness of several units in the army, led by (the) artillery corps."

The drill was not previously announced, but the military said it had been scheduled.

"The drill is a part of routine inspection in the army," the statement said. "These drills take place throughout the year."

Military sources said the drill began with soldiers being drafted from their homes, after which they were dispatched by air to the Golan Heights, which borders Syria.

The drill was to end with a live fire exercise later in the day, sources added.

"The drill was scheduled in advance and does not indicate any changes in the army's levels of alert," they said.

Israel is closely watching its northern border with Syria, where the embattled regime has reportedly considered supplying chemical weapons to the Lebanon-based militant group Hezbollah.

Tensions also remain high over the prospect of a preemptive Israeli strike against Iran's nuclear programme, which the Jewish state believes masks a weapons drive.

On Sunday, the head of Iran's Revolutionary Guards General Mohammad Ali Jafari warned that if Israeli jets or missiles did strike Iran, "nothing of Israel will be left."

Israel, the Middle East's sole, if undeclared, nuclear power, believes Tehran is using its nuclear programme as cover for building atomic weapons.

Iran denies the charge, saying the programme is for peaceful civilian energy and medical purposes.