"We are hearing a clear desire from all concerned to de-escalate the situation and respect calm and I appeal for an end to acts of violence," Robert Serry, U.N. Special Coordinator for the Middle East Peace Process, said in a statement.

Rocket and mortar fire from Gaza have increased in the run-up to the second anniversary of Israel's devastating Gaza offensive which began on December 27, 2008 and rocked the enclave for three weeks before an unofficial ceasefire.

On Thursday one Palestinian was killed and three were wounded in the northern Gaza Strip when they approached the border fence at a point Israel has declared off limits, Gaza medical officials said.

Palestinian hospital sources said the dead man was a shepherd and those wounded were another shepherd and two men sifting through rubble. Gaza hospital sources also said 13 Palestinians had been killed in cross-border hostilities with Israeli forces this month.

Reuters