NATO doubled down on Tuesday on its commitment to one day include Ukraine, a pledge that some officials and analysts believe helped prompt Russia’s invasion this year. The world’s largest security alliance also pledged to send more aid to Ukrainian forces locked in battle with Russian troops.

Ukraine’s supplies of spare parts for its battered electricity grid are running out amid sustained Russian bombing. European companies are being asked to urgently donate surplus kit to help the country get through the winter, after the latest step in Russian bombings targeting power plants and substations resulted in power cuts lasting 48 hours or more across the country.

Ukraine’s state energy operator, Ukrenegro, has said it is still struggling to restore full power nearly a week after Russian strikes damaged energy facilities across the country. The power deficit was running at 30% as of 11am local time on Tuesday, Ukrenegro said in a statement, a slight rise from the previous day after emergency shutdowns at several power plants and an increase in consumption as winter sets in.

Russia’s deputy foreign minister, Sergei Ryabkov, said Moscow had been left with “no other choice” but to cancel nuclear weapons talks with the US, state-run news agencies reported. He said it was unlikely any meeting would take place this year.

Ukraine has detained a deputy head of newly liberated Kherson’s city council on suspicion of aiding and abetting Russian occupation forces, Ukraine’s state prosecutor has said. The official, who was not named, cooperated with the occupation authorities and helped with the functioning of public services under the Russians, according to the prosecutor.

The G7 group has agreed to set up a network to coordinate investigations into war crimes, as part of a push to prosecute suspected atrocities in Ukraine. In a joint declaration, G7 justice ministers said member countries would ensure there is a central national contact point in each state for the prosecution of international crimes.