The US president says he was "very surprised" with the attitude of the United Kingdom towards the war.
"Two weeks ago I said 'why don't you send some ships over' and he [Keir Starmer] really didn't want to do it," Trump says, BBC reports.
Trump says he told Starmer, "you're our oldest ally" and stresses that he's supported the UK's efforts in Ukraine.
"Then they tell us that we have a mine ship around and they don't want to do it, I think it's terrible," he adds. "We requested two aircraft carriers which they have and he didn't really want to do it."
Trump then suggests that Starmer eventually offered to send aircraft carriers to the Middle East, but says this was already "after the war had ended".
"I was not happy with the UK," he says. "I think they'll be involved maybe, but they should be involved enthusiastically."
