Ukraine has used US weapons to strike inside Russia in recent days, according to a western official.

The weapons were used under recently approved guidance from US President Joe Biden, allowing American arms to be used to strike inside Russia for the limited purpose of defending Kharkiv, Ukraine’s second-largest city.

The official spoke on condition of anonymity.

Mr Biden’s directive allows for US-supplied weapons to be used to strike Russian forces that are attacking or preparing to attack.

It does not change US policy that directs Ukraine not to use American-provided ATACMS or long-range missiles and other munitions to strike offensively inside Russia, US officials have said.

Ukrainian officials had stepped up calls on the US to allow Kyiv’s forces to defend themselves against attacks originating from Russian territory.

Kharkiv is just 12 miles from the Russian border and has come under intensified Russian attack.

In advancing in the northeast Kharkiv region, Russian forces have exploited a lengthy delay in the replenishment of US military aid.

In addition, western Europe’s inadequate military production has slowed crucial deliveries to the battlefield for Ukraine.