Israel has released some of the tax money it collected on the Palestinian Authority's behalf but withheld after Hamas's election victory last year.

The first instalment of funds being sent to the government of Palestinian President Mahmoud Abbas amounts to about $50 million US, according to the Associated Press.

However, a senior Palestinian official told the Reuters news agency the payment totalled $120 million, enough to pay government employees' salaries for one month.

Israel has refused to transfer about $600 million to the Palestinians since Hamas took office in March 2006, following a January vote.

The funds were expected to arrive in the West Bank town of Ramallah by Monday, according to officials in the office of Abbas's prime minister, Salam Fayyad.

Israel accelerated efforts to support Abbas after Hamas routed his Fatah movement and seized the Gaza Strip last month.

The infighting has left the Palestinians with two rival governments — the isolated militant regime in Gaza and Abbas's emergency cabinet in the West Bank.

Israel has sealed off Gaza from the outside world since the takeover, because Hamas's charter calls for the destruction of the Jewish state.

Since forming an emergency government, Abbas has been trying to consolidate his secular Fatah party's hold on power in the West Bank by firing civil servants who are Hamas loyalists.

The tax funds account for roughly half of the Palestinian government's operating budget. Without the money, the government has been unable to pay regular salaries to its 165,000 workers.

Since the government is the largest employer in the Palestinian territories, the sanctions have crippled the Palestinian economy.

Israel is planning to transfer all frozen taxes in several instalments over the next six months, government officials said.

With files from the Associated Press