UNITED NATIONS, April 8 (Xinhua) -- UN Secretary-General Antonio Guterres on Wednesday unequivocally condemned Israel's massive strikes across Lebanon earlier in the day, his spokesperson said.

UN Secretary-General Antonio Guterres (File photo: Xinhua)

"The Secretary-General strongly condemns the loss of civilian lives and is deeply alarmed by the mounting toll on civilians," Stephane Dujarric said in a statement, referring to the hundreds of civilians, including children, killed or injured by the strikes.

The ongoing military activity in Lebanon poses a grave risk to the U.S.-Iran ceasefire and the efforts toward a lasting and comprehensive peace in the region, he added.

"The Secretary-General reiterates his call to all parties to immediately cease hostilities," he said, stressing that international law must be respected at all times, civilians and civilian objects must be protected at all times, and attacks directed against them are unacceptable.

Underscoring that there is no military solution to the conflict, Dujarric said the secretary-general continues to call on all sides to avail themselves of diplomatic channels and recommit to the full implementation of Security Council resolution 1701.