Britain says it is donating long-range ‘Storm Shadow’ missiles to Ukraine.

Britain is donating long-range Storm Shadow missiles to Ukraine to help it reclaim territory lost to Russia since the start of its invasion, Britain’s defense secretary, Ben Wallace, told Parliament on Thursday.

The missiles, which are launched from the air, are the latest in a pipeline of military aid delivered to the country by Britain, the United States and other NATO allies. Mr. Wallace said he would not detail the weapon’s capabilities.

“Ukraine has a right to be able to defend itself,” Mr. Wallace said. “The use of Storm Shadow will allow Ukraine to push back Russian forces based within Ukrainian sovereign territory.”

Ukraine has asked for longer-range missiles. It was unclear what the effective range of the Storm Shadow missiles would be, or when the missile would arrive in Ukraine.

Since last summer, Ukraine has made extensive use of HIMARS weapons, short for High Mobility Artillery Rocket System, supplied by the United States, in part to target concentrations of Russian military infrastructure and troops.