British Prime Minister Andy Burnham told Ukrainian President Volodymyr Zelensky on Tuesday that "we are behind you and that will not change" during a Downing Street meeting aimed at reinforcing allied support as the US signals a shift in policy.

Zelensky traveled to London following US President Donald Trump's calls for Ukraine to replace its leader and Trump's announcement of sanctions relief on Russian diesel. Trump said the move aims to reduce global fuel costs ahead of US elections in November.

Burnham acknowledged the "dark and difficult" circumstances Ukraine faces, citing "heavy bombardment" and widespread power outages. Ukrainian officials reported overnight Russian missile and drone strikes left at least 600,000 people without electricity. The Ukrainian military said for a second consecutive night it did not receive advance warning from allies of the incoming strikes.

No. 10 announced it would accelerate delivery of lightweight multirole missiles to Ukraine, which Ukrainian forces have used against Russian drones.

Zelensky said Ukraine survives "because we have strong partners" and called Britain "one of the strongest partners in our history." Burnham greeted the Ukrainian president with a hug and provided an honor guard upon his arrival.

The Trump administration has proposed an energy ceasefire, which Burnham said Ukraine is willing to discuss. Russia has responded with "further attacks on critical national infrastructure in Ukraine," according to the prime minister.

Zelensky has suggested the US threatened to restrict intelligence-sharing unless he agreed to the energy ceasefire proposal. Trump has denied withholding information.

At Prime Minister's Questions, Liberal Democrat leader Sir Ed Davey asked Burnham if he agreed with characterizing Trump's actions as a "shameful betrayal." Burnham declined to directly criticize the US president, saying his role required being "careful in terms of laying the ground to bring people back together" to restore allied support. He told MPs that Zelensky would not leave Britain "empty-handed."