China strongly condemned Wednesday an Israeli air strike in Lebanon that killed a Chinese United Nations observer, demanding Israel do more to ensure UN peacekeepers are not harmed in the conflict.

"The Chinese side is deeply shocked and strongly condemns this," foreign ministry spokesman Liu Jianchao said in a statement, referring to Tuesday's strike in the town of Khiam in which up to four UN observers were killed.

"The Chinese side demands that all sides in the confrontation, especially Israel, take all measures to ensure the safety of UN peacekeepers."