TEHRAN, July 12  -- A Chinese Middle East envoy on Saturday called for an immediate ceasefire between Israel and the Palestinians as their five-day clashes have caused heavy casualties.

Special envoy Wu Sike said China is deeply concerned about the escalating conflict between the two sides, which should be resolved through peace talks.

Tensions along the Israel-Gaza border have been mounting after Israel blamed Islamist militant group Hamas in the Gaza Strip for the abduction and murder of three Jewish teenagers last month.

The Israeli airstrikes on the coastal enclave in retaliation for a barrage of rocket attacks has claimed 156 lives and wounded 1,065 others since Tuesday.

China has been opposed to the use of force against civilians and believed that the tit-for-tat violence will only deepen their hatred and hostility, Wu told the Chinese media in Iran.

The ongoing conflict highlighted the importance and urgency of resumption of Israeli-Palestinian talks, he said, calling on both sides to exercise utmost restraint.

The Chinese envoy is on a Middle East tour, which has taken him to Iraq and Turkey.