The United Kingdom is sending multiple Storm Shadow cruise missiles along with other long-range weapons to Ukraine ahead of its anticipated counteroffensive against Russia's forces, according to senior Western officials.

U.K. Defense Secretary Ben Wallace is expected to announce to the House of Commons that the missiles are being sent to Ukraine, reports CNN.

The Storm Shadow, developed by the U.K. and France, is described as having stealth capabilities and a firing range of 250 kilometers or 155 miles. It is usually launched from the air and has a range capability just short of the U.S.-made surface-to-surface Army Tactical Missile Systems (ATACMS) Ukraine has been seeking for some time.

"The U.K. has previously said that it will supply Ukraine with long-range weapons," an unnamed Western official told CNN. "The British Government has been clear that this is only in response to Russia's deliberate targeting of civilian national infrastructure and is a proportionate response."

Storm Shadow missiles have enough range to strike into Russian-held territory in Eastern Ukraine, and a Western official said the Ukrainian government has assured the U.K. that the missiles will only be used inside Ukraine's sovereign territory and not to strike targets inside Russia.

The U.K. considers Crimea as being Ukraine's sovereign territory, calling it "illegally annexed" by Russia.

A senior U.S. military official commented that the Storm Shadow missiles are "a real game changer from a range perspective."

Currently, Ukraine's maximum range from weapons provided by the United States is only around 49 miles.

But even with the deployment of the Storm Shadow missiles, Ukraine President Volodymyr Zelenskyy is saying his country needs "a bit more time" before launching the counteroffensive, intended as an attempt to reclaim Russian-held territory in the eastern and southern sections of Ukraine, as it is still waiting for more promised Western aid to arrive.

"With [what we have] we can go forward and be successful, but we'd lose a lot of people," he told European public service broadcasters for an interview published Thursday. "I think that's unacceptable."

• Blaine Holt to Newsmax: No US Strategy for Ukraine Aid
• Vatican: Peace Mission Underway to End War in Ukraine