Speaking alongside NATO chief Mark Rutte, who was visiting Paris in the wake of Donald Trump's reelection as US President, Macron said he was "delighted" that other nations were falling in line with his longstanding call to collectively invest more in defence.

"It's the agenda of European strategic autonomy that will allow us to have more money, to build capacity and autonomy for the Europeans, and an ability to cooperate with our non-European allies as part of the alliance," Macron said.

Trump has questioned Washington's commitment to defend NATO allies and spoken of slashing support to Ukraine or striking a deal with Russia to end its years-long invasion.

His return to the White House is a renewed spur to Europeans -- long used to conventional and nuclear protection from the US military -- to reexamine their own defence.

"Nothing should be decided about Ukraine without the Ukrainians, nor about Europe without the Europeans," Macron said, adding that "building up homegrown military capacity would be "a long-term effort."

He joined Rutte in calling North Korean troops' appearance alongside Russian soldiers "a serious escalation" in the Ukraine conflict that widened the threat to the Pacific, increasingly the Americans' priority theatre.

"Russia, working together with North Korea, Iran and China, is not only threatening Europe, it threatens peace and security, yes here in Europe, but also in the Indo-Pacific and North America," Rutte said.

"We must stand together -- Europe, North America and our global partners... We have to keep our trans-atlantic alliance strong," he added.

Rutte pointed to backing Russia has received from Iran, North Korea and China.

"We must do more than just keep Ukraine in the fight. We need to raise the cost for (Russian President Vladimir) Putin and his enabling and authoritarian friends by providing Ukraine with the support it needs to change the trajectory of the conflict," he told reporters.