Nato boss gives verdict on Ukraine’s chances of breakthrough by winter

However, Kyiv has made progress – albeit slowly – and Moscow has seen its combat effectiveness undermined by the number of tanks and other vehicles destroyed

Ukraine’s offensive against Russian forces is making slow progress, and there may not be a major breakthrough of Russian lines in the next two months as had previously been envisaged, according to Western officials.

However, “focusing on such tactical issues” is counterproductive and there is a need to look at the bigger picture, the officials said, adding that this shows that Vladimir Putin is losing the war, as Ukraine has retaken a sizeable amount of territory overall since Russia’s invasion began.

Nato’s secretary general Jens Stoltenberg confirmed that Ukraine is making progress in its efforts to regain territory that began in June, contradicting Mr Putin’s claims this week that the counteroffensive “has failed, not stalled”.

“The Ukrainians are gradually gaining ground... They have been able to breach the defensive lines of the Russian forces, and they are moving forward,” Mr Stoltenberg said in an update to MEPs at the European Parliament on Thursday.

“The Ukrainian offensive is slower than we anticipated a couple of months ago,” one Western official said. “That is an acknowledgement of Russian defences. And it’s also an acknowledgement of how Ukraine is having to pull together a force that is a mixed fleet of both old equipment and donated equipment ... and a civilian population that has been thrown to the fore and doing some of the toughest things in land warfare, which is getting through a minefield.” Mines form a layer of Russia’s defences.

“Russia has lost either killed or wounded over 270,000 people and [destroyed] over a couple of thousand tanks, and if you add that to armoured fighting vehicles [then it is] over 4,000 fighting vehicles,” the official added.

“There has been an enormous drain on Russia, and particularly its army and its combat effectiveness,” the official said. “And then in the broadest base, you’re seeing Russia under economic pressure and under diplomatic pressure.”

Armour supplied by the West, including German Leopard tanks, has been damaged or destroyed in the prolonged battles continuing in the east and south across the last three months. The first of 14 Challenger II tanks provided by Britain was put out of action near Zaporizhzhia this week.

According to defence sources, it was immobilised by a mine and then targeted by a Russian Lancet loitering drone. There are no plans, sources say, to replace it at present from within the 145 Challenger IIs currently available for deployment.

The Western officials said that arms supplies to Kyiv will continue, and denied that “war fatigue” will begin to spread unless Volodymyr Zelensky’s government can show significant success in the near future. That is something that has been suggested by a number of European politicians.

It has also been argued that the Kremlin is banking on American support for Ukraine starting to fray as the US presidential campaign gets under way next year. The possibility of Donald Trump – who was accused of being the “Muscovian candidate” when he was previously in the White House – winning the election greatly adds to this concern.

“Russia thinks time is on its side; we think time is on our side,” another official said. “It has been put that if you’re Putin, you’re gambling that Donald Trump wins the next [US] election. But that is quite a long way away.”