It is highly unlikely that Britain or its allies will send troops to defend Ukraine if it is invaded by neighbouring Russia, the defence secretary, Ben Wallace, has said. US intelligence claims that Russia has stationed about 70,000 troops near the border of Ukraine and has begun planning for a possible invasion as soon as early next year. Wallace and the Ukrainian defence minister, Oleksii Yuriyovych Reznikov, issued a joint statement on 16 November which said they were “concerned” by Russia’s military buildup. “The United Kingdom stands shoulder to shoulder with the people of Ukraine and will continue its longstanding determination to support them,” the statement added. But in an interview with the Spectator, Wallace said Ukraine “is not a member of Nato so it is highly unlikely that anyone is going to send troops into Ukraine to challenge Russia”. “We shouldn’t kid people we would. The Ukrainians are aware of that,” he added, in comments carried by the Times before the interview’s publication. Asked if that meant Ukraine was on its own, Wallace said: “We can all help with capacity building but to some extent Ukraine is not in Nato and that is why we are doing the best diplomatically to say to Putin don’t do this.” It comes days after Boris Johnson told the Russian leader, Vladimir Putin, there would be “significant consequences” for Russia if it invaded Ukraine. The prime minister spoke by telephone to Putin on Monday to reassert the UK’s commitment to Ukraine’s territorial integrity and warn that any destabilising action by Moscow would be a “strategic mistake”. The Kremlin has denied preparing an invasion and has accused the government in Kyiv of stoking tensions in the region by deploying new weapons. The two countries have been at odds since 2014 when Russian forces annexed the Crimean peninsula and backed a separatist rebellion in eastern Ukraine.