PM Rishi Sunak to announce Britain's largest-ever military aid package for Ukraine

April 22 (UPI) -- Prime Minister Rishi Sunak is to travel to Poland on Tuesday when he will announce Britain's largest-ever military aid package for besieged ally Ukraine.

The package will include some 400 vehicles, 1,600 strike and air defense missiles and 4 million rounds of ammunition as well as $617.8 million in additional military funding, his office said Monday.

The additional funding is on top of the $3 billion Britain has earmarked for Ukraine this year.

"Defending Ukraine against Russia's brutal ambitions is vital for our security and for all of Europe," Sunak said in a statement. "If [Russian President Vladimir] Putin is allowed to succeed in this war of aggression, he will not stop at the Polish border."

Among the package is Storm Shadow precision-guided missiles, which Britain says are the first long-rang munitions an ally has sent to Ukraine amid its two-year war against Russia.

The prime minister's office called it "our largest-ever single package of equipment."

"We will never let the world forget the existential battle Ukraine is fighting," Defense Secretary Grant Shapps said in a statement, "and with our enduring support, they will win."

In Poland, Sunak is to hold his in-person meeting with Prime Minister Donald Tusk of Poland. The two are expected to discuss deepening their two countries' relations. The pair will also hold talks in Warsaw with NATO Secretary-General Jens Stoltenberg on European Security and Ukrainian support.

The announcement comes after the U.S. House of Representatives passed legislation that includes some $61 billion for Ukraine's military late last week after months of stalling by Republicans.

The bill will now be combined with three other national security supplementals passed on Saturday and be sent to the Senate for approval, which is expected, before it can be sent to President Joe Biden for his signature.

President Volodymyr Zelensky of Ukraine met with a bipartisan delegation visiting Ukraine on Monday, and thanked them for deciding on the military support.

Ukraine has for months said it was running out of supplies amid the deadlock on funding in Congress, and he told the U.S. lawmakers Monday that Kyiv is "in absolute need of air defense."

"We urgently need concrete assistance with this. We also need very specific weapons to help the military and protect civilians. Of course, we are talking about the need for weapons with a longer range," he said. "Artillery shells are also very important."

Following his visit to Poland, Sunak will head for Berlin to meet with Chancellor Olaf Scholz of Germany. They will discuss security trade and diplomatic ties with European allies, his office said.