Rishi Sunak refused to support Ben Wallace today over the Defence Secretary's criticism of Ukraine's attitude to war support from the West.

The Prime Minister faced questioning in the Commons over remarks by Mr Wallace, in which he said he told Kyiv he was 'not Amazon' when it came to weapons supplies.

Speaking at a Nato conference in Lithuania the Defence Secretary also suggested president Zelensky show more 'gratitude' for materiel support in order to counter opposition mainly in the United States to funding weapon supplies.

Mr Sunak spoke in the Commons today about the conference he also attended in Vilnius, which discussed Ukraine's desire to join the alliance.

Labour shadow minister Alex Sobel, who also chairs the Ukraine APPG (all-party parliamentary group), said: 'Ukraine is not just defending itself, it is defending the UK and people right across Europe. 

'So I was disappointed to hear the Defence Secretary say that he is 'not Amazon'. Does the prime minister disassociate himself from those comments?'

But in a sight of his displeasure at the comments, Mr Sunak did not speak in support of his minister, replying instead: 'President Zelensky and the people of Ukraine are incredibly grateful for all the leadership and support shown by the UK Government, and indeed the British people.'

It came after the Ukrainian war leader had expressed his frustration at the reluctance of the 31 member states to agree a firm timetable for membership at the gathering in the Baltic.

Speaking in Vilnius Mr Wallace said he had bluntly told told Kyiv officials 'I'm not Amazon' when he was presented with a 'shopping list' of weaponry and supplies after an 11-hour drive to visit the war-torn capital. 

He told reporters: 'There is a slight word of caution here which is that, whether we like it or not, people want to see gratitude.'

'My counsel to the Ukrainians... you're persuading countries to give up their own stocks. And yes the war is a noble war and yes we see it as you doing a war for not just yourself but our freedoms.

'But sometimes you've got to persuade lawmakers on the Hill in America. You've got to persuade doubting politicians in other countries that it's worth it and it's worthwhile and they're getting something for it.'

His critique followed one issued by a senior adviser to Joe Biden. US National Security Advisor Jake Sullivan said:

'I think the American people do deserve a degree of gratitude from the United States government for their willingness to step up and from the rest of the world as well.'

In a thinly-veiled swipe at Zelensky's criticism of his Western allies, Sullivan said some of the charges leveled against the U.S. were 'entirely unfounded and unjustified.'

The United States is by far the largest donor of military support to Ukraine, offering more than $46 billion worth of hardware to Kyiv, according to data from a respected German think-tank.

Lawmakers in Congress have earmarked as much as $100 billion, but not all of that aid has yet been drawn down to help the Ukrainian government. 

Most of the weapons shipped to Ukraine are also made in the U.S., boosting jobs in the country's key defense sector.

The second largest donor, by contrast, is Britain, which has offered up just over $6 billion, according to the Kiel Institute for the World Economy's Ukraine Support Tracker.

A bemused Mr Zelensky later said he was 'always grateful' for foreign aid, adding: 'I don't clearly understand the questions. We were always grateful to the UK, to the prime ministers and to the minister of defence.'

Labour's shadow defence secretary John Healey said: 'The Ukrainians are fighting for the future and the freedom of their country.

'President Zelensky wants more military help yesterday, of course he does. What he doesn't need is lectures on gratitude, especially when they overshadow a successful summit in which NATO is stronger and the support for Ukraine is greater.'