Qatari aid money is expected to be delivered to the Gaza Strip in the coming days after Israel blocked its delivery over protests along the fence, the AFP news agency reported citing a source close to the Qatari ambassador.

The Israeli media reported on Thursday that the country's security cabinet had agreed to permit the money to be brought to Gaza after temporarily blocking it, but there was no official confirmation.

Mohammed al-Emadi, the ambassador of Qatar to Gaza, entered the strip through the Erez crossing from Israel late on Wednesday, the source reported.

But he arrived without the $15m to be used to pay to Hamas civil servants and provide support for impoverished Gazans.

"We expect the third payment to be allowed to enter Gaza in the coming days," the source said without giving more details.

The ambassador was expected to bring the funds with him, but Israeli Prime Minister Benjamin Netanyahu decided to block the delivery on Wednesday, according to an Israeli official.

The decision was made after the Israeli troops reportedly came under fire on the Gaza border on Tuesday, with one soldier receiving minor injuries when a bullet struck his helmet.

Israel hit back with tank fire and an air raid on Hamas military posts.

Israel and Hamas have fought three wars since 2008 and fears of a fourth one remain, although violence has abated since November under an informal truce.

Under the agreement, Israel has allowed Qatar to bring in aid to the strip, including $15m a month to pay salaries of Hamas civil servants and assist impoverished residents.

The payment would be the third of six planned tranches, totalling $90m, in connection with the truce.

Israel's permission is required since the cash must be delivered via its territory.

Hamas, which rules the Gaza Strip, is labelled a "terrorist organisation" by the United States and the European Union, and banks are hesitant to make the transfer.

Israel has also allowed Qatari-financed fuel to enter Gaza to help ease a severe electricity shortage in the blockaded enclave.