The UK has announced a fresh round of sanctions against the "Russian military and Kremlin elites."

It comes as Ukrainian President Volodymyr Zelensky made a surprise visit to Britain on Wednesday.

The sanctions package targets six entities providing military equipment, such as drones, for Russia’s invasion of Ukraine, as well as eight individuals and one entity connected to "nefarious financial networks that help maintain wealth and power amongst Kremlin elites," a government statement reads.

"Ukraine has shown Putin that it will not break under his tyrannical invasion. He has responded by indiscriminately striking civilian areas and critical national infrastructure across the country," UK Foreign Secretary James Cleverly said in the statement.

"We cannot let him succeed. We must increase our support," he added.

"These new sanctions accelerate the economic pressure on Putin – undermining his war machine to help Ukraine prevail," said Cleverly.

"I am determined, consistent with our laws, that Russia will have no access to the assets we have frozen until it ends, once and for all, its threats to Ukraine’s territorial sovereignty and integrity."After arriving in London earlier Wednesday, Zelensky met with UK Prime Minister Rishi Sunak. The Ukrainian president is due to address British lawmakers and meet with King Charles later.