VILNIUS British Defence Secretary Ben Wallace said on Wednesday he had warned Ukraine that its international allies were "not Amazon" and Kyiv needed to show gratitude for weapons donations to persuade Western politicians to give more.

London has been one of Kyiv's staunchest supporters since Russia's invasion last year, and Prime Minister Rishi Sunak has said Britain and its allies will double down its support for Ukraine.

But Wallace warned that Ukraine had to persuade U.S. lawmakers and "doubting politicians in other countries that it's worth it", and that "whether we like it or not, people want to see gratitude".

Wallace was speaking on the sidelines of the NATO summit in Lithuania in response to a question from a reporter about Ukrainian President Volodymyr Zelenskiy's complaints that Kyiv had not been given a timeline for joining the alliance.

Wallace recalled that he had travelled last year to Ukraine, where he was presented with a shopping list of weapons.

"You know, we're not Amazon," he said, referring to the giant American tech and retail company. "I told them that last year, when I drove 11 hours to be given a list."

On Wednesday Zelenskiy softened his tone, saying that the results of the summit had been good even if there had not been a formal invitation for Ukraine to join NATO, and that he had received positive news on defence packages from allies.

Asked about Wallace's comments, Sunak said that Zelenskiy had been grateful for the support given so far and that more support would be forthcoming as required.

"President Zelenskiy has expressed his gratitude for what we have done on a number of occasions," Sunak told a press conference at the summit in Vilnius.

"I completely understand Volodymyr's desire to do everything he can to protect his people and to stop this war, and we will continue to give him the support that he needs."

(Reporting by Andrew Gray in Vilnius, additional reporting by Kylie MacLellan in London, writing by Alistair Smout and Mark Heinrich)