Washington (CNN) President Donald Trump and Israeli Prime Minister Benjamin Netanyahu made their debut Wednesday as chummy partners preparing to tackle the Middle East's toughest challenges side by side.

Netanyahu beamed at his new American counterpart and declared him the best friend Israel could possibly wish for, while Trump offered lofty praise for Israel, denounced the Iranian nuclear deal and declined to back a two-state solution -- a longstanding, bipartisan US policy that the Israeli Prime Minister has questioned.

The encounter signaled a warmer chapter in US-Israel relations than Netanyahu had enjoyed with Trump's predecessor. After eight years of grappling with President Barack Obama, Netanyahu embraced a like-minded counterpart at the White House.

But Trump also made clear that he would not give Israel carte blanche, taking a harder line on some issues than he had during the campaign.

"I'd like to see you hold back on settlements for a little bit," Trump told his counterpart, the most direct indication from the Trump administration of its stance on the controversial issue.

Trump delivered the message as a polite request rather than an official warning but still represented a public demand from a White House that had previously been more open to settlement building that other US administrations. During Trump's campaign, he encouraged Israel to "keep going" with settlement construction.

Trump also stepped back from other components of his campaign's rhetoric endorsing Israel's positions on several sensitive issues.

He said Wednesday he'd "love" to see the US Embassy move to Jerusalem but offered no indication it would happen in the near future, as he had promised before he stepped into office. And he made no mention of his campaign pledge to recognize Jerusalem as the "undivided" capital of Israel, another campaign promise.

While Trump offered some insight into how his administration will tackle the Israeli-Palestinian conflict, he avoided drilling down on specifics.

He did not specify whether his request that Netanyahu "hold back on settlements" applied only to the construction of new settlements, or the expansion of existing ones -- and whether it applied to those in East Jerusalem.

Trump struck an optimistic tone as he announced his intention to broker a lasting peace to end the decades-old conflict that has stumped his predecessors.

"The United States will encourage a peace, and really a great peace deal. We'll be working on it very diligently -- very important to me also," Trump said. "But it is the parties themselves who must directly negotiate such an agreement."

He declined to offer any specific positions, however, instead backing away from the major tenet that has guided recent administration in how to resolve the conflict: a two-state solution, one for Israelis and one for Palestinians.

"I'm looking at two state and one state, and I like the one that both parties like," Trump said. "If Israel and the Palestinians are happy, I'm happy with the one they like the best."

Trump then called on Israel to "show some flexibility" in striking a deal and said Palestinians "have to get rid of some of the hatred they're taught at a very young age." Trump also signaled that Arab countries would be invited to help with negotiations to "make it easier" to achieve a peace deal.

"I also believe that we're going to have other players at a very high level and I think it might make it easier on Palestinians and others," he said.

Netanyahu, for his part, sought opportunities to draw closer to his new American counterpart.

He praised Trump for his strong stance against Islamic extremism, saying, "Under your leadership, I believe we can reverse the rising tide of radical Islam."

Trump also hit themes of importance to Israel concerning the wider region. He repeated a frequent criticism of the deal between Tehran and six world powers worked out under the Obama administration, which Trump called "one of the worst deals I've ever seen."

"I will do more to prevent Iran from ever developing -- I mean ever developing -- a nuclear weapon," Trump said, referring to recent sanctions slapped on the country for a missile launch.

And Trump vowed that the US would guard Israel from any negative action at the United Nations, which Trump said has treated Israel "very, very unfairly." In one of its last actions, the Obama administration refrained from vetoing a resolution at the UN Security Council condemning Israel for its settlement expansion.

JUST WATCHED On GPS: Is anti-Semitism on the rise in US? Replay More Videos ... MUST WATCH On GPS: Is anti-Semitism on the rise in US? 02:23

Asked by an Israeli reporter about the rise in anti-Semitic incidents in the US since his election and any connection to the support his campaign received from bigoted groups, Trump first touted his electoral victory before pledging he will "do everything in our power to stop long-simmering racism and other things going on."

The Anti-Defamation League slammed the response, tweeting: "Troubling that @POTUS failed to condemn real issue of anti-Semitism in US today."

But Netanyahu backed Trump on the issue, blunting criticism on a key issue that has troubled some in the Jewish community.

"There is no greater supporter for the Jewish people and the Jewish state than President Donald Trump," Netanyahu said. "We should put that to rest."