NATO membership row | Can understand why there is 'fear' of Ukraine joining NATO, says Zelensky

US President Joe Biden will have a "straightforward and candid" discussion with Ukrainian President Volodymyr Zelensky after the Ukraine-NATO Council meet, the White House said.

The leaders will discuss the rationale for NATO's decision to not give a clear timeline for Ukraine to join Nato.

Zelensky had criticised NATO for what he sees as delays in setting out Ukraine's membership timeline, calling it "unprecedented and absurd" on Tuesday.

Biden "knows that President Zelensky has strong views and isn't afraid to express those views," White House national security adviser Jake Sullivan said in an interview with MSNBC.

Asked about the US supplying the controversial cluster bombs to Ukraine, Zelensky thanked President Joe Biden for agreeing to deliver them.

He said that he understands people have a different view on the use of the munitions, which are banned by more than 120 countries, including many NATO allies.

He, however, added that people should view the move "from a position of fairness", noting that Russia has "constantly" deployed the destructive explosives on Ukraine's territory since invading last year.

He clarified that they plan to only use the weapons on military targets in occupied territories.

The press conference has now concluded and both leaders head off to the first meeting of the NATO-Ukraine council.

Ukrainian President Volodymyr Zelensky said that he expects Ukraine to join NATO once Russia's war ends, after alliance leaders refused to set a timeline for membership.  

"I am confident that, after the war, Ukraine will be in NATO. We'll be doing everything possible to make it happen," Zelensky said, at a news conference at the NATO summit in Vilnius.

"But the biggest risk is if President Putin wins, because then the message is if you use military force, when he violates international law, when he invades a neighbour, then he gets what he wants," he chief adds.

Stoltenberg says this is the biggest danger to NATO, confirming his view that Ukraine has the right to choose its own path and alliances.

"We can never allow that Moscow starts to decide who can and cannot be a member of Nato. Russia has been against every enlargement of Nato.

"It's for Nato allies and Ukraine to decide when to become a member, Moscow doesn't have a veto on that."

He agreed that Ukraine cannot be a member of the alliance while a war is going on within its border. But, he adds, "signals are important".

Article 5 of NATO's charter states that if one member is attacked, it is deemed to be an assault on all and hence all others must come to its defence.

He says it's difficult as partners are living under under different conditions, whereas in Ukraine "survival" matters.

He said that he is grateful to those leaders who helped with the package and for the "important steps" on simplifying the process for Nato membership for Ukraine.

He adds Ukrainian soldiers have proven democracy is stronger than "terrorist attacks" from Russia

He said that they will hold crisis consultations and take decisions jointly.

"Ukraine is now closer to Nato than ever before," he adds.

He also recapped Nato has simplified the plan for Ukraine to join - but only when conditions are met.

Stoltenberg said Putin also underestimated the unity and strength of ATO's members in the face of his invasion.

NATO boss said the military alliance will continue to stand with Ukraine as long as it takes, adding Nato has already provided tens of billions of dollars worth of support over the last year.