Ukrainian President Volodymyr Zelenskyy has warned that the U.S. formally siding with Russia’s Vladimir Putin would be a “historic mistake,” but said he still sees President Donald Trump as an ally despite a series of moves that have unsettled his country and its friends on Capitol Hill.

“We want to trust him,” Zelenskyy told NBC News’ “Meet the Press” on Sunday, referring to Trump. “I hope that he will change his decisions, because I think that it’s all mistakes, and it will not help us, and it will not help United States.”

Trump on Friday waived sweeping new sanctions against Russia passed by Congress, saying in an executive order that the move “is in the national interests of the United States.” Passed with bipartisan support and signed by Trump last month, the sanctions were intended to target Russia’s revenue streams by punishing global buyers of Russian oil and gas.

The waiver came days after a deal with Putin to release hundreds of thousands of tons of Russian diesel fuel onto the global market as fuel prices soar.

At the same time, Zelenskyy said, U.S. intelligence sharing was briefly “blocked,” blinding Ukraine to incoming ballistic missiles, while limits have been placed on Starlink technology critical to intercept jet-powered drones.

Zelenskyy told moderator Kristen Welker that Ukrainian officials believe the decision to limit Starlink, imposed by Elon Musk’s SpaceX, came in response to a “message from American government.”

The U.S. has been Ukraine’s most significant backer across four and a half years of war, but personal relations between Trump and Zelenskyy have appeared severely strained in recent weeks, with each offering public criticisms of the other.

Asked about Trump’s remark this week that the Ukrainian leader was “more difficult to deal with than Putin,” Zelenskyy said he was “very honest” with Trump.

“Maybe it’s not very polite,” he said, but it is “better to have partners who are very open and clear than to have those who are killers, even with a smile on their face.”

Zelenskyy, who accused the U.S. of betraying Kyiv last week, said that his feelings have not changed. He warned that Trump’s diesel deal with Russia “will strengthen Putin in his will to occupy us.”

Announcing the deal week, Trump expressed hopes that it would go some way to address soaring fuel costs.

But Zelenskyy said the deal wouldn’t have “a real influence” on the price of oil in the U.S. because the rising prices were due to the blockage of the Strait of Hormuz, not Ukraine.

“I don’t know all the reasons why President Trump makes such deals,” he said.

Of the prospect of the U.S. more formally siding with Russia, he said: “If these two countries will be together ... we will not prevail, and we will not be able to stand.”

Zelenskyy said it was a “pity” Trump had waived the sanctions in a bill named for the late Sen. Lindsey Graham, R-S.C., who he said was “a great supporter of peace and of Ukraine.”

“He invested his life and time because he really believed in Ukraine,” he said.

The war has seen little recent movement on the frontline, with Russia continuing to occupy around a fifth of Ukraine. Trump had vowed to end the conflict within days of his second term, but peace talks have effectively stalled, with Ukraine saying that Russia has rejected a short-term ceasefire and that Putin’s terms for peace are tantamount to a full surrender.

Meanwhile, another difficult winter looms for Ukrainian civilians, with a critical munitions shortage limiting Zelenskyy’s ability to defend infrastructure against Russian strikes.

Zelenskyy said he was due to speak to U.S. negotiators by phone later Sunday and was still hopeful of a meeting in the days ahead. “I’m very open for this, even with all the difficult circumstances,” he said.

He cited some progress after a multiday interruption to U.S. intelligence about incoming Russian ballistic missiles, which he said has now been “deblocked.”

“We are very thankful for this,” he said. “Now it works.”

European and Ukrainian officials previously told NBC News they believed that a move to limit sharing intelligence, coming only days after Trump eased sanctions on Russia, were most likely aimed at pressuring Kyiv into making concessions at the negotiating table amid a stalemate in peace talks.

While Zelenskyy indicated that the intelligence problem has been resolved, he said that Ukraine was still facing an ongoing speed restriction on its use of Starshield, the military version of the Starlink service.

Asked if he thought Trump or Musk had directly made the decision to limit Starlink, Zelenskyy said that he didn’t know but thought “both” were involved. He said that if Trump decided tomorrow to lift the restriction, “it will immediately work as it was before.”

The White House did not immediately respond to a request for comment.