The UK has reportedly agreed to allow Ukraine to use British-supplied Storm Shadow missiles for long-range strikes deep into Russian territory, according to a report by The Guardian on Thursday.

Citing unnamed UK officials, the report suggests that this significant shift in policy has been made behind closed doors, though no official public announcement is expected.

The decision comes amid ongoing discussions between Kyiv and its Western allies about the restrictions placed on the use of long-range weapons.

Ukraine has long maintained that such restrictions limit its ability to defend itself and push back against Russian forces.

However, Washington has been wary of allowing Ukraine to target deep inside Russia, fearing it could escalate the conflict further.

During a joint press conference in Kyiv on Wednesday, US Secretary of State Antony Blinken and UK Foreign Secretary David Lammy reiterated that Russia bears responsibility for the war's escalation.

Blinken, who avoided directly addressing any changes in US policy regarding long-range strikes, stated that the US has adapted its strategy "from day one" and remains open to doing so.

He did not comment on the potential use of Storm Shadow missiles by Ukraine.

The timing of Blinken and Lammy's visit to Kyiv—on the heels of Washington's confirmation that Iran has delivered ballistic missiles to Russia—adds further significance to the meeting.

Blinken described the new arms supply to Moscow as providing Russia with "additional capability and flexibility" in its ongoing war against Ukraine.

While there was no explicit confirmation from Blinken about a shift in US policy regarding long-range strikes, the report from The Guardian noted that such a decision might be made quietly.

The UK officials believe the visit to Kyiv by top US and UK diplomats likely wouldn't have gone ahead without some level of agreement on expanding Ukraine's capabilities with Storm Shadow missiles.