Austin's trip -- which follows a visit to Israel by Secretary of State Antony Blinken -- will also include meetings with defence officials and the country's emergency government, the US official said Thursday.

Hamas gunmen killed 1,200 people in Israel and took about 150 hostages in their surprise onslaught from Gaza on Saturday. Israel has retaliated by raining air and artillery strikes on Hamas targets in Gaza for six days, claiming over 1,350 lives.

Washington responded by sending an aircraft carrier and other warships to the eastern Mediterranean and promising munitions and other equipment to Israel.

Austin told journalists in Brussels on Thursday that the United States had no "early warnings or indications" that the Islamist group would launch its bloody assault.

He also said Washington has not placed any conditions on the way Israel can use the weapons it provides.

"This is a professional military, led by professional leadership, and we would hope and expect that they would do the right things in the prosecution of their campaign," he said.

Israel has prepared for a possible ground invasion of the Palestinian territory after what has been labelled Israel's 9/11.

Fears have grown for Gaza's 2.4 million people now enduring the fifth war in 15 years in the coastal enclave, which has also seen Israel cut off water, food and power supplies.