BRUSSELS >> Ukrainian President Volodymyr Zelenskyy said Thursday his country has intelligence information that 10,000 troops from North Korea are being prepared to join Russian forces fighting against his country, warning that a third nation wading into the hostilities would turn the conflict into a “world war.”

Zelenskyy did not go into further details about the claim that came a day after U.S. Deputy Secretary of State Kurt Campbell said in Seoul that Washington and its allies are alarmed by North Korea’s military support for Russia’s war in Ukraine but couldn’t confirm Ukrainian claims that North Korean soldiers were sent to fight for Moscow.

“We know about 10,000 soldiers of North Korea that they are preparing to send (to) fight against us,” Zelenskyy said, calling any North Korean involvement “the first step to a world war.”

The Ukrainian leader’s comments raised the stakes for his Western allies as he met with European Union leaders and then NATO defense ministers to discuss his “ victory plan “ to end the country’s devastating war with Russia.

“If we start now and follow the victory plan, we can end this war no later than next year,” he told the EU leaders.

He told reporters the plan aims “to strengthen Ukraine” and pave the way for a diplomatic solution to end the conflict on Europe’s eastern flank.

“This plan doesn’t depend on Russian will, only on the will of our partners,” he said before addressing leaders at an EU summit.

Zelenskyy was later shuttling across Brussels to meet with NATO defense ministers. The EU is a key supporter of Ukraine, a candidate member of the 27-nation bloc, as it fights Russia’s invasion that began more than 2 1/2 years ago.

Zelenskyy outlined the five-point plan to Ukraine’s parliament on Wednesday without disclosing confidential elements that have been presented in private to key allies, including the United States.

Major points of the plan include an invitation for Ukraine to join NATO and permission to use Western-supplied longer-range missiles to strike military targets deep inside Russia, steps that have been met with reluctance by Kyiv’s allies so far.

“If we get this sign that we will be in NATO, we will feel that we are not alone,” Zelenskyy said.

Hungarian Prime Minister Viktor Orbán, widely seen as having the warmest relations of any EU leader with Russian President Vladimir Putin, called Zelenskyy’s plan “more than frightening” in a Facebook post and said he would urge major EU powers France and Germany to “begin negotiations with the Russians as soon as possible, in order to find a way out of this situation.”

The Institute for the Study of War in Washington said that Putin is seeking to draw out the war and he believes “that Russian forces can outlast Western support for Ukraine and collapse Ukrainian resistance by winning a war of attrition.”

NATO Secretary-General Mark Rutte said Thursday that Kyiv can rest “absolutely assured that 32 allies are united in making sure that collectively, we will do whatever is needed to make sure that Ukraine can prevail, that (Russian President Vladimir) Putin will not get his way.”

Rutte reiterated that Ukraine’s place is among NATO’s ranks, but he would not say when it might join. Zelenskyy insists that a membership invitation is central to his “victory plan” and would provide his country with the ultimate security guarantee to protect it from Russia.

“Ukraine will be a member of NATO in the future,” Rutte said. “The question is exactly about the ‘when.’ I cannot answer that now.”

However, Rutte said, Putin must understand that “we are in this, if necessary, for the long haul. And obviously we want to be in a place where Zelenskyy and Ukraine, from a position of strength, is able to start talks with Russia.”

Zelenskyy told EU leaders that his troops must keep battling Russian forces in Ukraine “while also bringing the war back into Russia so that Russians can feel what war is like and begin to hate Putin for it.”

Zelenskyy said he needs to “move some partners forward” on the issue. “And I think only with the unity in EU we can move and can move not only EU leaders, we can move other leaders.”

A draft copy of EU summit conclusions — a text that will likely be tweaked before publication at the end of Thursday’s meeting — reaffirms the bloc’s “unwavering commitment to providing continued political, financial, economic, humanitarian, military and diplomatic support to Ukraine and its people for as long as it takes and as intensely as needed. Russia must not prevail.”