US President Donald Trump has discussed the possibility of withdrawing from NATO, raising fresh uncertainty over the future of the transatlantic alliance.

Speaking at a White House briefing on Wednesday, press secretary Karoline Leavitt criticised NATO’s response to the recent US and Israeli war with Iran, describing it as a “test” the alliance had failed.

She said member states had declined to provide direct military support beyond defensive measures, Al Jazeera reported.

“They were tested, and they failed,” Leavitt said, quoting Trump.

She added that it was “quite sad that NATO turned its back on the American people”, who she said had long funded the alliance’s defence.

Her remarks came shortly before Trump met NATO Secretary-General Mark Rutte at the White House. Leavitt said the president was preparing for a “frank and candid conversation”.

After the meeting, Rutte described the talks as “frank and open” in an interview with CNN.

While acknowledging US frustration, he said NATO allies had provided support through logistics and access to military bases.

Asked whether Trump had raised withdrawing from NATO or reducing support, Rutte said there was “a disappointment” but noted the US president had listened to his arguments.

He also reiterated his support for Trump’s leadership.

Trump has long had a strained relationship with NATO, alternating between criticism and reassurances of US commitment.

Since returning to office in 2025, he has renewed pressure on European allies to increase defence spending.

At the 2025 NATO summit, members agreed to nonbinding targets to raise defence budgets to 5 per cent of GDP by 2035, though tensions persisted, including disputes with Spain over exemptions.

Relations were further strained by Trump’s past threats to take control of Greenland, which he argued was vital to US security, drawing strong opposition from European leaders.

Following the launch of the US-Israeli war against Iran in February, Trump also criticised European allies for not contributing more actively to the campaign.

According to a report by The Wall Street Journal, the administration is now considering reducing its military footprint in Europe, including the possible closure of bases or troop withdrawals from countries such as Spain and Germany.

When asked whether the US could leave NATO, Leavitt said the option had been discussed and could be addressed following Trump’s talks with Rutte.

Rutte, who has met Trump multiple times during his second term, has previously warned that NATO “will not work” without US support.