A ceasefire in the Gaza Strip is attainable within days if the smuggling routes which supply arms and money to Hamas can be shut down, international envoy Tony Blair has said.

Mr Blair said that the Hamas movement, which holds power in the Palestinian enclave, is in contact with Egypt over the issue and that Cairo is prepared in principle to take action. All "responsible" players in the region should be working towards an immediate cessation of the hostilities which have now entered their 11th day, he said.

The former Prime Minister was speaking in Jerusalem after an intense night of fighting in Gaza as Israeli forces expanded their ground and air offensive.

Israel continued to ignore mounting international pressure for a ceasefire in the assault, which has claimed more than 500 lives, around a quarter of them civilians, according to the United Nations.

Israeli troops have fought pitched gun battles with Hamas militants as they targeted strategic buildings and smuggling tunnels linking the tiny enclave with Egypt.

Mr Blair, who on Monday spoke to Israeli Foreign Minister Tzipi Livni, told BBC Radio 4's Today programme: "There are circumstances in which we could get an immediate ceasefire, and that is what people want to see.

"These circumstances focus very much around clear action to cut off the supply of arms and money through the tunnels that go from Egypt into Gaza.

"I think if there were strong, clear, definitive action on that, that gives us the best context to give us an immediate ceasefire and start to change this situation.

"From my conversations, not just with Tzipi Livni but the Israeli Prime Minister and Defence Minister and others, I think that is the one basis on which we could bring a quick halt to this. Otherwise, I think we are in for a protracted campaign."

Mr Blair, who is the envoy of the Middle East Quartet of the UN, US, EU and Russia, said that talks on the issue were ongoing within the international community and between Israel and Egypt. And he said that, while he and other international representatives refuse to speak to Hamas, the movement's leadership in Gaza was well aware of the position from their own discussions with Egypt.