WASHINGTON, May 20 (Reuters) - President Joe Biden on Thursday (May 20) pledged humanitarian and reconstruction aid for Gaza as he hailed a deal to end 11 days of fighting between Israel and Hamas that tested his negotiating skills and exposed him to criticism from fellow Democrats.

Biden, appearing briefly at the White House after news of the ceasefire agreement, also promised to replenish Israel's Iron Dome missile defence system, despite complaints from the Democratic left about a pending US arms sale to Israel.

Biden said the United States would work through the United Nations and other international stakeholders "to provide rapid humanitarian assistance and to marshal international support for the people in Gaza and in the Gaza reconstruction efforts".

He insisted that reconstruction aid would be provided in partnership with the Palestinian Authority and not with Hamas, which the United States labels a terrorist organisation.

The Palestinian Authority, which is run by moderate President Mahmoud Abbas, only governs parts of the occupied West Bank, however, while Hamas holds sway in the Gaza Strip.

"We will do this in full partnership with the Palestinian Authority - not Hamas - in a manner that does not permit Hamas to simply restock its military arsenal," Biden said.

State Department spokesman Ned Price said Secretary of State Antony Blinken would travel to the region in coming days to meet Israeli, Palestinian and regional counterparts to discuss recovery efforts and "working together to build better futures for Israelis and Palestinians".

The ceasefire agreement followed days of intense diplomatic activity that provided a test of the ability of Biden and his top national security aides to help resolve a conflict that could have spiralled into a prolonged war.

During the negotiations, Biden spoke to two leaders with whom he has had tense relations - six times with Israeli Prime Minister Benjamin Netanyahu, including twice on Thursday, and once with Egyptian President Abel Fattah al-Sisi.

Both Netanyahu and Sisi were close to Biden's Republican predecessor, Donald Trump. Biden waited weeks to call Netanyahu after taking office in what Israel viewed as a snub.

His phone call with Sisi on Thursday was the first time they had spoken since Biden took office in January. Egypt, which has a peace treaty and diplomatic relations with Israel and also maintains contacts with Hamas, has traditionally played a key role in quelling Gaza fighting.

The absence until now of direct communication between the two presidents had been widely seen as a snub of Sisi by a new administration that has made clear its concerns about Egypt's human rights record.