Israel has agreed to a temporary ceasefire proposed by the United Nations after four young Palestinian boys were killed in a strike on a Gaza beach.

The development came as Palestinian president Mahmoud Abbas travelled to Egypt in an effort to keep talk of a longer ceasefire in Gaza alive.

“Between 10:00 and 15:00 (local time on Thursday) , the Israel Defence Forces will cease operational activity within the Gaza Strip and hold its fire,” the Israeli military said in a statement.

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UN special coordinator for the Middle East peace process Robert Serry had earlier told Israeli TV that he had asked the military for a “humanitarian pause” in its Gaza offensive and that, if it agreed, he would ask Gaza militants to follow suit.

“If it happens, I will also call on Hamas and other militant factions to reciprocate, stop firing rockets and respect the humanitarian pause,” his spokeswoman quoted him as saying.

“It is in the interest of all the citizens of Gaza, in order to give them a chance to go to the hospital, get health care or get food.”

Militant group Hamas said it was considering the request.

“Hamas has been informed about the UN proposal for a truce of several hours tomorrow,” Hamas spokesman Sami Abu Zuhri said.

“The proposal is being studied and when a decision has been taken it will be announced officially in a statement.”

Israel’s attacks on Gaza continued ahead of the ceasefire, with several more Palestinians killed, while Hamas militants continued to fire rockets at Israeli cities.

In one incident, four boys aged between eight and 11 were killed on a Gaza beach. They were said to be playing football when they were hit by Israeli fire in full view of several foreign journalists.

Israel’s military said the deaths appeared to be the “tragic outcome” of an Israeli strike targeting Hamas militants.

“Based on preliminary results the target of this strike was Hamas terrorist operatives,” it said in a statement.

“The reported civilian casualties from this strike are a tragic outcome.”

Israel said it would it will investigate the incident.

The death toll in the conflict has now risen to more than 200 people, all but one of them Palestinian.

The United States is doing “everything in our power” to end the bloodshed in the Gaza Strip, secretary of state John Kerry said.

“Our concern is to have a legitimate ceasefire and see if we can find a way to stop the conflict and killing so we can get to the real issues that are underlying it,” Mr Kerry said as he met his counterpart from Luxembourg.

“And we’re doing everything in our power.”

He added that he had been speaking to Israeli prime minister Benjamin Netanyahu and Arab officials.

Egypt’s efforts to broker an end to the violence collapsed on Tuesday when Hamas, which rules Gaza and has fired more than 1,200 rockets into Israel, rejected the proposal on the grounds that it was not included in talks.

The US state department said Mr Kerry in the past day had spoken to the foreign ministers of Egypt, Qatar and the United Arab Emirates – which are seen as holding influence with Hamas – and to Arab League secretary-general Nabil al-Arabi.