June 6, 2022, 7:01 a.m. ET

Credit…Ints Kalnins/Reuters

The British military announced on Monday that it would send its most sophisticated multiple-launch rocket system to Ukraine, joining the United States in providing much-needed long-range artillery at a time when Russia is using its vast weaponry to hit Ukrainian positions across the eastern front.

“As Russia’s tactics change, our support for Ukraine must change,” said British Defense Secretary Ben Wallace.

The announcement comes days after the Biden administration said it would provide Ukraine with its most advanced multiple-launch rocket system and munitions in hopes of giving the country an edge over Russia.

President Volodymyr Zelensky and other top Ukrainian officials have been advocating for such weapons for months, but it could take weeks more before they have an impact on the battlefield. Ukrainian soldiers must be trained to use the systems, which are far more advanced than anything currently in Kyiv’s arsenal.

The use of overwhelming and often indiscriminate force allowed the Russians to make limited gains in eastern Ukraine. Moscow forces pounded targets on the 75-mile eastern front line on Monday, according to the Ukrainian military.

At present, the Russian artillery can go beyond the weapons available to the Ukrainians, allowing the Russian forces to rain down shells day and night, without the Ukrainians being able to retaliate effectively. The roadblocks have taken a heavy toll on the Ukrainian military: the Ukrainian government has said that up to 100 soldiers die every day.

The moves by the United States and Britain mark the latest escalation in an ever-increasing flow of weapons from the West to Ukraine since Russia’s full-scale invasion in late February.

The United States began sending heavy artillery to Ukraine in April. As of May 26, a senior US Department of Defense official said he had delivered 85 M777 howitzers to Ukraine, along with 190,000 projectiles for use in these weapon systems.

Multi-rocket launch systems supplied by the United States and Britain provide Ukraine with the ability to hit Russian targets at a much greater distance and with greater accuracy.

The US High Mobility Artillery Rocket System, or HIMARS, can hit targets nearly 50 miles away and is capable of firing satellite-guided rockets that carry about the same explosive power as a 500-pound bomb dropped from the air. .

Britain’s M270 multiple rocket launcher system offers similar capabilities, Mr Wallace said, adding that they “will enable our Ukrainian friends to better protect themselves against the brutal use of long-range artillery, which the forces of Putin have used indiscriminately to raze cities”. ”

Before supplying the weapons, the Ukrainians had promised the United States that they would not use the long-range rockets to attack targets inside Russia. The BBC reported that the British government had received similar assurances.

In remarks carried by Russian state media on Sunday, Mr Putin dismissed US weapons, saying they were “nothing new”, but at the same time warned that if Russia felt threatened, it would “would hit facilities that we are not”. attack so far.