Donald Trump said he was "very angry" to hear reports of an alleged Ukrainian drone strike on one of Vladimir Putin's state residences in Russia.
Sergei Lavrov, Moscow's long-serving foreign minister, said Kyiv launched the attack on Putin's home in the Novgorod region overnight on Sunday, but that all 91 drones used were shot down by Russian air defences.
Ukrainian President Volodymyr Zeleskyy hit back against the claims, calling them "lies".
Asked about the reports while welcoming Israeli Prime Minister Benjamin Netanyahu to his Mar-a-Lago estate in Florida on Monday, Mr Trump said it was "not good".
"I learned about it from President Putin today. I was very angry about it," he said, describing his second phone call with the Russian leader in as many days as "very good".
"It's a delicate period of time," he added. "This is not the right time. It's one thing to be offensive, because they're offensive. It's another thing to attack his house. It's not the right time to do any of that."
US 'hit' Venezuela docks
Taking questions from the media alongside Mr Netanyahu, Mr Trump also confirmed the US "hit" a dock area in Venezuela where he alleged drugs were loaded onto boats.
This would mark the first known time the US has carried out operations on land in Venezuela since a pressure campaign began against the government of President Nicolas Maduro several months ago.
"There was a major explosion in the dock area where they load the boats up with drugs. They load the boats up with drugs. We hit all the boats, and now we hit the area," Mr Trump said, without providing any further details.
It was not immediately clear what target was hit, nor which part of the US government acted.
Asked if the CIA had carried out the attack, Mr Trump said: "I don't want to say that. I know exactly who it was, but I don't want to say who it was."
Warning sent to Iran
With Mr Netanyahu arriving in Mar-a-Lago for talks concerning the Middle East, Mr Trump was quizzed on reports Iran is stepping up the rebuilding of its ballistic missile programme, despite the reintroduction of UN sanctions last month banning such activity.
"I hear that Iran is trying to build up again, and if they are, we're going to have to knock them down, we'll knock them down, we'll knock the hell out of them," Mr Trump said.
"But hopefully that's not happening. I heard Iran wants to make a deal. If they want to make a deal, that's much smarter.
"You know, they could have made a deal the last time, before we did a big attack on them."
He adds: "I think, again, they should make a deal. They want to make a deal. But sometimes that doesn't happen."
Hamas 'must disarm'
Mr Netanyahu is also seeking further US support in Gaza, where there has been little movement on the complex second phase of the Israel-Hamas truce, raising concerns that both sides are failing to take action to carry out the next phase of the deal.
More than 400 people have been killed in Gaza since that agreement, local officials say, while Israel has accused Hamas of ceasefire violations, including the delayed return of hostage remains - with one body still to be handed over.
Asked how quickly the ceasefire agreement can move to its second phase, Mr Trump said: "As quickly as we can, but there has to be a disarmament.
"We have to disarm with Hamas. It's one of the things we'll talk about, certainly, but there has to be a disarming of Hamas."
(c) Sky News 2025: Alleged strikes on Vladimir Putin residence 'not good', Donald Trump says
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