WASHINGTON, May 23 (Reuters) - Republican U.S. House Speaker Mike Johnson said on Thursday Israeli Prime Minister Benjamin Netanyahu would soon address a joint meeting of Congress amid heightened tension with President Joe Biden over the Israeli leader's handling of the war in Gaza.

Delivering a keynote speech at the Israeli embassy's annual Independence Day reception, Johnson, the top congressional Republican and a critic of the Democratic president’s Israel policy, said it would be “a strong show of support for the Israeli government in their time of greatest need.”

Such a speech is sure to further anger progressive Democrats critical of Israel's military campaign in Gaza and Biden's support for it. Netanyahu has closely aligned himself with Republicans.

The diplomatic gathering in Washington comes amid strains between Biden and Netanyahu over a U.S. push for Israel to do more to protect Palestinian civilians in the war against Hamas militants in Gaza.

The embassy gave equal billing to Democratic U.S. Representative Pete Aguilar, who shared the high-profile platform with Johnson at a more subdued event under the shadow of the Gaza war. "As Americans, we reaffirm our commitment to Israel's sovereignty," he said.

Speaking first, Johnson said to applause: "Tonight I'm happy to announce ... we will soon be hosting Prime Minister Netanyahu at the Capitol for a joint session of Congress."

Successive U.S. administration have usually sent a high-level official to the Independence Day receptions.

Vice President Kamala Harris, who in recent months has called the situation in Gaza a "humanitarian catastrophe" and has urged a ceasefire, delivered last year's keynote, mostly extolling U.S. backing for Israel.

An Israeli official said this year the embassy wanted to honor lawmakers in a bipartisan way in appreciation for congressional approval of billions of dollars in new U.S. military aid.

The reception took place on the same night as a White House state dinner for Kenyan President William Ruto, which the Israeli official said created a scheduling conflict for cabinet members.

Several less senior Biden aides were in attendance, including Derek Chollet, Secretary of State Antony Blinken's counselor.

The White House declined comment when asked whether it was consulted about the invitation to Netanyahu or whether Biden, who has denied an Oval Office meeting to the Israeli leader, might see him in Washington.

Johnson and Aguilar both condemned the International Criminal Court prosecutor's decision this week to seek arrest warrants for Netanyahu and his defense chief, Yoav Gallant. The prosecutor also asked for warrants to capture Hamas leaders responsible for the deadly Oct. 7 cross-border attack on Israel, which triggered the Gaza war.

Johnson took a veiled swipe at Biden, saying "some leaders" have sought to withhold "vital weapons" from Israel. Biden has paused one shipment of bombs and warned he could delay others if Netanyahu carries out an all-out ground offensive in the refugee-packed city of Rafah in southern Gaza. But the flow of weapons has mostly continued.

Security was tight around the National Building Museum where the reception was held. A small group of pro-Palestinian protesters shouted "shame on you" at guests exiting the event. One person held an Israeli flag stained red to simulate blood. Another on a megaphone accused Israel of war crimes.

On Tuesday, Johnson said he was close to inviting Netanyahu, a right-wing leader who had warm relations with former President Donald Trump.

Johnson, a Trump ally, had issued Senate Majority Leader Chuck Schumer an ultimatum to sign a letter inviting Netanyahu or else he would only speak to the House of Representatives.

Schumer had signaled he was open to Congress hosting Netanyahu, despite declaring in March that the Israeli leader had “lost his way” and calling for new elections in Israel.

Johnson did not specify a date for Netanyahu's speech.

Addresses to Congress are a rare honor generally reserved for the closest U.S. allies.

Netanyahu has already given three speeches, most recently in 2015. That year, Republican leaders invited him without consulting Democratic then-President Barack Obama, as Netanyahu joined them in an unsuccessful bid to derail Obama's international nuclear deal with Iran.

Dozens of Democrats boycotted Netanyahu's last speech, raising the prospect that some could stay away this time.

Johnson, struggling to keep his fractious Republican House majority intact, has been a prominent voice in the U.S. political divide over Israeli policy. Politicization of the issue has intensified ahead of the November election in which Biden is running against Trump.

In contrast to past years’ gala celebrations, this year’s reception, marking the 76th anniversary of Israel’s founding, was billed as a “solidarity event.”

Israel is fighting to wipe out Hamas militants who attacked Israel on Oct. 7, killing 1,200 people and seizing 253 hostages, according to Israeli tallies.

Palestinian authorities say more than 35,000 people have been killed during Israel's campaign in Gaza.

Photo from Reuters