Amid the to-ing and fro-ing of world leaders and diplomats between Moscow and other European capitals last month, one visit particularly stood out.

Striding across the polished floors of Russia’s ministry of defence, Ben Wallace, the UK’s Defence Secretary, was pictured grim-faced in conversation with Sergei Shoigu, his counterpart in Vladimir Putin’s government.

Behind them, Admiral Sir Tony Radakin, the recently-installed chief of the defence staff, and General Valery Gerasimov, Russia’s chief of the general staff, walked side-by-side in their respective military dress.

Supplementing the more customary visits from diplomats and foreign ministers, Mr Wallace, a former captain in the Scots Guards, wanted to deliver a specific message to the minister and military chief in charge of Russia’s armed forces.

“I managed to say to Shoigu and Gerasimov, the Ukrainians will fight and we will sanction you,” Mr Wallace said in an interview with The Telegraph, almost a month after his trip.

While privately believing that Vladimir Putin, the Russian president, had already resolved to invade Ukraine, Mr Wallace said: “I felt it was important that they heard from one of probably the biggest military powers in Europe, and one of the two nuclear powers in Europe, what we thought was acceptable and not acceptable, and that we were not prepared to be intimidated.”

He said he also talked of “my own experience of dead soldiers” and said “I don’t want anyone to die”, adding: “I don’t want Russian soldiers to die any more than I want Ukrainians to die.”

It was, said Mr Wallace, a “very professional” and “straight” encounter – apart from the Russians’ assurance “that they were not going to invade Ukraine”.