UK Prime Minister Rishi Sunak has requested an evaluation of the war's development in Ukraine, according to BBC Newsnight. 

According to BBC, senior officials worry that the PM is being unduly cautious as the war enters a crucial phase. According to a Whitehall source, the exercise resembled a "Goldman Sachs dashboard" analysis of the conflict and the use of UK military supplies.

Downing Street insists that Sunak is strongly supportive of Ukraine, according to the report. Sunak said in a tweet the UK was with Ukraine "all the way" during a visit to the country last month, his first overseas trip as prime minister.

The British Prime Minister was not being too cautious, the Downing Street official continued, and "the UK government's support for Ukraine is unwavering."

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However, some parts of Whitehall are concerned about the request, because military leaders believe that Ukraine's access to weaponry could be crucial throughout the coming winter.

The Whitehall source said: "Wars aren't won [by dashboards]. Wars are won on instinct. At the start of this, it was Boris (Johnson) sitting down and saying: 'Let's just go for this.' So Rishi needs to channel his inner Boris on foreign policy, though not of course on anything else."

According to the source, the audit, also known as a data-driven evaluation, is intended to evaluate the state of the conflict and the importance of the UK's military support for Ukraine. It said: "This is about looking at what we have put in, what we have got out."

It is worth noting that the UK is one of the largest suppliers of military aid to Ukraine since the beginning of the war. 

BBC Newsnight reveals that the Ukrainian president is aware of the debate within the UK and is encouraging Sunak to maintain strong military support for his country. "President Zelensky has sensed what is going on," the source said.

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"So he has been talking to Rishi. He is trying to inspire him, saying the UK are the great liberators, the great fighters. We need you. Rise to that."

The recommended evaluation of the war is being offered at a pivotal time in the conflict. Whitehall insiders are of the opinion that Ukraine and Russia are at a halt in their conflict.