Plans for a British and French peacekeeping force in Ukraine will require “serious numbers” of troops to face down Russia, a former army chief has warned.
Sir Richard Shirreff, who served as Nato’s deputy supreme allied commander in Europe between 2011 and 2014, said allied forces would need to “overmatch” Russia to ensure they could fight back if Vladimir Putin’s country broke a ceasefire agreement.
But he suggested this would not be possible under Britain’s current level of defence spending, warning: “A government without a sword is useless.”
Sir Richard’s assessment was shared by former defence secretary Sir Gavin Williamson, who said Britain would need to deploy around 40,000 troops to ensure the operation was effective. Last year, figures showed there were around 147,000 people in the UK armed forces, with just over half assigned to the army.
On Tuesday, Britain and France signed a historic agreement committing to boots on the ground in Ukraine as soon as any ceasefire with Russia comes into place.
The document, signed at a summit in Paris by Keir Starmer, French president Emmanuel Macron and Ukrainian president Volodymyr Zelensky, has been hailed as “a significant step forward” in using the so-called coalition of the willing to guarantee peace in the war-torn country.
German chancellor Friedrich Merz also suggested his country could soon sign up to sending troops to Ukraine.
Sir Richard told the BBC’s Today programme that about 50,000 troops were sent to Kosovo by Nato in 1999 and that country was “pocket-sized” in comparison to Ukraine.
“Any reassurance or enforcement force from Britain, France and other partners that is deployed to Ukraine has got to be capable of overmatching Russia,” he said. “Because Russia, even if it is forced into accepting a ceasefire, will absolutely, as sure as eggs is eggs, break that ceasefire.
“So any reassurance force has got to be capable of facing down Russia, and if necessary, being able to fight Russia. And this means serious capabilities, serious numbers, and a properly joined-up military organisation.”
Asked if that meant “thousands and thousands” of personnel who would then not be able to be deployed to emergencies elsewhere, he said: “Absolutely. I mean, if you think about the size of the frontline in Ukraine… the intervention force that was put into Kosovo by Nato in 1999, which was about 50,000, [and] Kosovo was a pocket-sized area compared to Ukraine. This requires serious numbers if it is to be effective.”
Sir Richard also hit out at the UK and other European countries over their levels of defence spending in recent years.
Sir Keir has pledged that the UK will spend 5 per cent of GDP on national security and defence by 2035, after bowing to pressure from President Trump on the issue.
But Sir Richard claimed Germany was the only country in Western Europe “putting any money into defence”, and warned a “government without a sword is useless”.
He added: “Western European countries, particularly this one, ducks and weaves and avoids and talks only.”
No 10 refused to say how many troops the UK could deploy to Ukraine. The PM’s official spokesperson said he would not “get into potential force structures. The only person that benefits is Putin”.
Asked if the PM was satisfied the British Army could deploy thousands of troops, he replied: “Of course we have complete confidence in the British Armed Forces”. It is understood that a number of countries, as well as Germany, have indicated that they are considering joining France and Britain.
Sir Keir has promised to hold a vote in the House of Commons, but No 10 would not guarantee that MPs could decide not to deploy troops. Asked if a “no” vote would be binding, the PM’s official spokesperson said: “I think we are getting ahead of ourselves”.
Speaking to The Independent, Sir Gavin warned that the UK would need to be far more ambitious than the 1,700 troops stationed in Estonia.
He said: “You are talking of at least 40,000 personnel, the equivalent of the army of the Rhine we had in Germany after the war. Of course, we cannot do that. We are talking about increasing the size of the army to 76,000 and we just do not have the personnel.”
The agreement to put boots on the ground in Ukraine was signed after President Trump’s son-in-law Jared Kushner confirmed the president “strongly, strongly, strongly” supported the security guarantees and would provide the backup to make it work.
But the apparent breakthrough comes as European countries scramble to react to President Trump laying claim to Greenland, the sovereign territory of EU Nato ally Denmark.
European leaders issued a statement declaring that “it is for Denmark and Greenland, and them only, to decide on matters concerning Denmark and Greenland”.
Sir Richard warned that the other countries that make up Nato without the US would be “really pushed” to defend Greenland from the US. He said it would be “suicide” for other Nato states to take on the US, and “total carnage”, but that he felt that outcome could be avoided.