Donald Trump has waived new sanctions on Russia, as the UK prepares to join a major wargame intended to demonstrate support for Ukraine.

The US president used his executive powers late on Friday to block a raft of tough new sanctions he had previously endorsed, claiming the move was in America’s “national interests”.

The move is the latest step in deteriorating relations between Mr Trump and Ukraine.

Earlier this month, the US president agreed to lift sanctions on Russian diesel in an effort to bring down fuel prices ahead of American mid-term elections that threaten significant losses for his Republican Party.

Mr Trump has also suggested Volodymyr Zelensky should be replaced as Ukrainian president, claimed he is “more difficult to deal with than Putin” and refused to say the Russian president was started the war.

The row has sparked concerns the US may have stopped sharing intelligence with Kyiv, and seen the Ukrainian military’s access to Elon Musk’s Starlink system restricted, inhibiting its ability to intercept Russian drone and missile attacks.

Ukraine’s access to Starlink has since been restored, and Mr Musk has claimed the decision to restrict it came ultimately from Mr Trump, which the president has denied.

While the US-Ukraine relationship frays, UK Defence Secretary Wes Streeting has announced that Britain will join Germany and France in a major military exercise in Poland next month.

Speaking in Washington DC, Mr Streeting said: “Ukraine is the front line for freedom everywhere, and it’s absolutely vital that they prevail against Putin’s aggression.

“We’re planning for the peace and freedom we want to see through our leadership of the coalition of the willing.”

The drill is aimed at ensuring Nato forces are ready to provide Ukraine with security guarantees once the war is over.

With 1,500 troops taking part, the exercise will simulate moving troops and supplies such as food and fuel, and was agreed at a coalition of the willing summit in July.

Meanwhile, Russia’s bombardment of Ukraine continues, with Kyiv reporting further strikes on Friday, wounding civilians, damaging homes and disrupting power supplies.

Russia has regularly targeted Ukraine’s energy grid in the lead-up to winter in an effort to “weaponise” freezing temperatures, and officials in Kyiv have warned Moscow is stockpiling missiles for more attacks over the coming months.