Israel has stepped up strikes and deployed ground troops to its northern neighbour since March 2, when Lebanon was dragged into the Middle East war after Tehran ally Hezbollah attacked Israel in retaliation for the killing of Iranian supreme leader Ali Khamenei.

"Two soldiers were killed in an Israeli strike while traveling by motorcycle on the Zibdin-Nabatyieh road" in south Lebanon, the Lebanese army said in a statement.

It had said earlier that another soldier died from wounds sustained in a strike on a car and a motorcycle in the same area that also injured four others.

An official from the military told AFP the soldiers had just finished their duties for the day.

The Israeli military said in a statement that it was "aware of the claim that several soldiers of the Lebanese Armed Forces were injured as a result of an IDF strike".

"The incident is under review," the army said, adding that Israeli forces were operating "against the Hezbollah terrorist organisation, and not against the Lebanese Armed Forces or Lebanese civilians".

While Lebanon's army has tried to stay out of the war, three Lebanese soldiers were killed by Israeli shelling earlier this month during a failed Israeli commando operation in eastern Lebanon.