PM Sunak to announce largest-ever military aid package to Ukraine during visit to Poland.

British Prime Minister Rishi Sunak will announce a 500-million-pound ($617 million) uplift in military support for Ukraine during his visit to Poland on April 23. The announcement will come with a warning that defeating Russia is imperative to halt any further advancement of its troops into Europe.

Sunak's trip to Poland to meet Prime Minister Donald Tusk marks his first international visit in months. The purpose is to demonstrate to his restless party that he remains in control ahead of an upcoming election, which many anticipate he will not win. Sunak will then travel to Germany to meet Chancellor Olaf Scholz in Berlin.

The U.K. has consistently voiced strong support for Ukraine, and the increased funding will bring London's total military assistance for this fiscal year to 3 billion pounds (roughly $4 billion). The action follows closely on the heels of the Ukraine aid approval by the U.S. House of Representatives.

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

The U.K. will send what it described as its largest-ever single package of equipment, including 60 boats, more than 400 vehicles, including 160 protected mobility ‘Husky’ vehicles, 162 armored vehicles and 78 all-terrain vehicles, over 1,600 strike and air defense missiles and nearly four million rounds of small arms ammunition.

"The United Kingdom will always play its part at the forefront of European security, defending our national interest and standing by our NATO allies," Sunak said.