Germany’s chancellor-in-waiting has asked for the protection of Britain’s nuclear deterrent if Donald Trump withdraws US security guarantees for Europe.

Friedrich Merz said Germany needed to prepare in case the president ditched Nato promises to defend his allies.

The centre-Right Christian Democratic Union (CDU) leader said he wanted Europe to have its own nuclear umbrella or at the very least be able to shelter behind Britain and France’s weapons.

Mr Merz is expected to win Sunday’s election and form its next coalition government at a time when there are fears the transatlantic relationship is breaking down.

Emmanuel Macron has already suggested the French deterrent could be extended to the rest of Europe, but has been rebuffed by Germany until now.

Since then, Mr Trump has begun negotiations with Russia over ending the war in Ukraine over Volodymyr Zelensky’s head, and without involving European leaders.

The US president has undermined Nato’s Article 5, which states an attack on one alliance member is an attack on all, after suggesting to Putin that he would abandon any ally not spending enough on defence.

Starmer stands with Ukraine

Sir Keir Starmer has joined the Europeans in criticising Mr Trump for calling Mr Zelensky “a dictator”.

For his trouble, the US president accused him of doing “nothing” to end the war in Ukraine.

Sir Keir will soon announce a new package of military aid for Ukraine, and sanctions on Russia, in a veiled rebuke to Washington.

In an olive branch to Mr Trump, the Prime Minister is expected to set the date of 2030 for British defence spending to hit 2.5 per cent of GDP when he visits the president on Thursday.

There are benefits to Britain offering Germany, and Europe, the shield of Trident.

Britain could prove to Washington that it is listening to the president’s demands that Europeans take responsibility for their own security.