A second Donald Trump presidency poses a risk to Ukraine in their fight against Russia, according to a former director of the CIA.

       John Brennan, who served as head of the intelligence service until 2017, says he is "worried" about poll data indicating a tight race between Trump and Democrat rival Joe Biden.

       Recalling a meeting with the Republican during his last term, Brennan said he felt Trump "wasn't quailfied then and isn't qualified now" - and highlights NATO and the US relationship with foreign allies as an area that could suffer.

       Prominent GOP members have called for a re-assessment of funding to Ukraine after a $47 million war chest supplied by Washington.

       And the former spy chief told France's RTBF he fears Trump could cut funding altogether.

       READ MORE: Russian military losses hit eye-watering financial sum in huge blow to Putin

       He said: "He can reduce or even stop financial and military aid to the government in Kyiv.

       "And that would give Vladimir Putin the green light to try to practically swallow Ukraine.

       "And unfortunately, I think that will encourage Putin to look hungrily at the rest of Europe."

       Brennan argues Ukraine and Europe would be safer under a second Joe Biden term. Biden, 81, and Trump, 78, are neck-and-neck in many leading polls.

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       In October, Trump claimed he would end the war in Ukraine within 24 hours of becoming President, were he to be re-elected in November.

       He said during a CNN Town Hall: "If I am President, I will have that war settled in one day, in 24 hours.

       "I will meet with Putin, I will meet with Zelensky; they both have weakness and they both have strengths.

       "And within 24 hours that war will be settled. It will be over."

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