As the war in Ukraine extends over its northern border with Russia, Kyiv is urging the United Kingdom and United States to authorise the use Western long-range missiles to strike deep into Russian territory.

Washington and London said they are now considering lifting restrictions to allow Ukraine to target Russian military sites after a meeting between US President Joe Biden and UK Prime Minister Keir Starmer in Washington, DC, on Friday.

Talk of authorising their use in Russia has enraged President Vladimir Putin, who said last week that doing so would mean NATO would be “at war” with his country.

For Storm Shadow missiles to be used, the UK, France, Italy and the US would be required to agree, given their involvement in manufacturing the weapons.

What are Storm Shadow missiles?

The Storm Shadow is an air-launched, long-range, conventionally armed missile designed to attack high-value fixed or stationary targets.

It is a Franco-British-developed weapon produced by MBDA (Matra BAe Dynamics Alenia), a European missile systems company also involving Italy. Storm Shadow is primarily produced by MBDA’s UK division using components from the US.

The missiles became operational in the UK and French air forces in 2003 and have been used in the Gulf, Iraq and Libya.

Storm Shadow missiles, also known as SCALP in France, weigh about 1,300kg (2,865lb), are 5.1 metres (16.7ft) long and have a range of up to 250km (155 miles).

Their system uses INS, GPS and terrain referenced navigation, and they are fitted with a blast/penetrator warhead, meaning they are able to operate in extreme conditions and can attack hardened or buried targets.

Each missile costs about $1m.

What places could Ukraine target?

Storm Shadow missiles would enable Ukraine to hit targets deep inside Russian territory with enough force to penetrate bunkers and ammunition stores.

Ukraine could potentially target locations such as Kursk, Millerovo and Rostov-on-Don.

What other long-range weapons does Ukraine have – and want?

Last May, the UK confirmed it had sent Ukraine Storm Shadows, but stressed that they came with conditions. The weapons were sent to be used only within Ukraine against Russian targets as the invasion continued. There are two further long-range weapons Ukraine has and wants.

ATACMS

The Army Tactical Missile System, known as ATACMS, fires a US-made, long-range missile with a range of up to 300km (190 miles).

According to US officials, Washington quietly sent ATACMS missiles with this range to Ukraine as part of a package of military support in March and Ukraine has used the weapons twice

Kyiv also received mid-range ATACMS missiles last year from the US. They have a maximum range of 170km (106 miles)

They can be launched from the M270 Multiple Launch Rocket System (MLRS) or the M142 High Mobility Artillery Rocket System (HIMARS), which Ukraine already has.

JASSMs

Joint Air-to-Surface Standoff Missiles, which are fired from F-16 fighter jets, have ranges of 370km (230 miles) to 1,000km (620 miles). They have not yet been provided to Ukraine, but earlier this month, the Reuters news agency quoted unnamed US officials as saying the Biden administration could soon announce it would supply Ukraine with JASSMs.

The weapons carry 455kg (1,000-pound) warheads. According to the US, official delivery of JASSMs might take months, and it is unclear whether Biden would allow Ukraine to fire these missiles into Russia.