BRUSSELS (Reuters) - NATO chief Mark Rutte said on Saturday he told Ukrainian President Volodymyr Zelenskiy that he needs to find a way to restore his relationship with U.S. President Donald Trump after their clash at a White House meeting on Friday.

The confrontation flared over differing visions of how to end Russia's three-year-old invasion, with Zelenskiy seeking strong security guarantees from a Trump administration that has embraced diplomacy with Vladimir Putin's Russia.

The meeting, which Rutte described as "unfortunate", plunged ties between Kyiv and its top military backer to a new low.

"I said: I think you have to find a way, dear Volodymyr, to restore your relationship with Donald Trump and the American administration. That is important going forward," Rutte told the BBC, commenting on a call he had with Zelenskiy on Friday.

He said he told Zelenskiy that "we really have to respect what President Trump has done so far for Ukraine", reminding Zelenskiy that Trump was the one who provided Javelin anti-tank weapons to Ukraine in 2019 that had enabled the country's forces to fight back after Russia's invasion.

"Without the Javelins in 2022, when the full-scale attack started, Ukraine would have been nowhere", said Rutte. "I told him we really have to give Trump credit for what he did then, what America did since then and also what America is still doing."

Quizzed on some of the accusations traded between the leaders on Friday, the NATO chief declined to comment in detail, saying the U.S. was very invested in the military alliance, including in its mutual-defence clause Article 5.

Rutte called Trump a friend but did not directly address questions about whether Trump was right when he accused Zelenskiy of gambling with World War Three, or when he said Zelenskiy either needed to strike a deal or the U.S. would be "out".

"I am absolutely convinced that the U.S. wants to bring Ukraine to this durable peace...And obviously, what they need to get there is to make sure that we'll all work together on this," he said.

Asked whether NATO allies would be capable of filling the gaps should the U.S. withdraw its military support from Ukraine, Rutte replied: "Let's move beyond this question. It is crucial that we stay all in this together - the U.S., Ukraine, Europe, that we bring Ukraine to a peace, this is exactly what President Trump is fighting for, what we all are fighting for."

(Reporting by Sabine Siebold; editing by David Evans, Editing by William Maclean)