Ukraine has begun using longer-range ballistic missiles against Russia that were secretly provided by the US, American officials have confirmed.

The weapons were sent as part of a previous US support package, and arrived this month. Officials said they were not announced publicly to maintain Ukraine’s “operational security”.

They have already been used at least once to strike Russian targets in occupied Crimea.

Further US aid is now heading to Kyiv.

More American weaponry is expected to be sent imminently, after President Joe Biden signed off on Wednesday a new package of economic and military support for Ukraine worth $61bn (£49bn).