Siniora asked UN peacekeepers tasked with monitoring the border, "to be careful" that Israel will not use the manoeuvres "to launch operations capable of increasing tension," a statement from his office said.

He also urged the Lebanese army to "be extremely vigilant and take the necessary measures to protect Lebanese civilians and face up to any Israeli violation" of Lebanese territory.

Siniora expressed concern that Israel could violate the terms of UN Security Council Resolution 1701 which was adopted to end the month-long war between the Shiite militant group Hezbollah and Israel in south Lebanon in 2006.

According to Siniora's office, General Claudio Graziano, the commander of the United Nations Interim Force in Lebanon, informed the Lebanese army that Israel was planning "unprecedented and massive military manoeuvres on April 6."

Israeli media have reported that the Jewish state will hold from Sunday a large-scale home front defence exercise featuring scenarios in which chemical and biological missiles hit populated areas.