Theresa May will travel to the Nato summit in Brussels this morning, where Western leaders wait to see what stance Donald Trump will take with US allies.
The US president has repeatedly demanded other Nato members step up their defence spending, but there are fears he could go further, including possibly threatening to pull US troops out of Europe or leave Nato entirely.
The row comes ahead of Mr Trump's visit to the UK later this week. Speaking before crossing the Atlantic, the Republican claimed the UK was "in turmoil" and said meeting Vladimir Putin may be easier than talks with Ms May. He also refused to say if he believed the prime minister should keep her job.
Ms May's trip to Brussels means she will miss Prime Minister's Questions. Her de facto deputy, David Lidington, will step in and go up against Labour's Emily Thornberry.
Questions are likely to focus on the ongoing row over the government's Brexit plan, with more Tory resignations a possibility as Eurosceptics continue to express their displeasure at the strategy agreed by ministers at Chequers.
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"The Chequers deal is a plan that has been put together, it's been agreed by government, we will be publishing our white paper this week which will set out more detail on it.
"It's there because it delivers on the vote that people gave on Brexit, it delivers the fact that we will have an end to free movement, we will have an end to the jurisdiction of the European Court of Justice in the UK, we won't be sending vast contributions to the EU every year, we'll be out of the Common Agricultural Policy, out of the Common Fisheries Policy.
"We deliver that Brexit and we do it in a way that protects jobs and livelihoods and meets our commitment to Northern Ireland.
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If the president wants to do it and he feels it’s appropriate to do it, he’ll make that decision'"I think it is very sad when Germany makes a massive oil and gas deal with Russia. We are supposed to be guarding against Russia and Germany goes out and pays billions and billions dollars a year to Russia.
We are protecting Germany, we are protecting France, we are protecting all of these countries and then numerous of the countries go out and make a pipeline deal with Russia where they are paying billions of dollars into the coffers of Russia. I think that is very inappropriate.
It should never have been allowed to happen. Germany is totally controlled by Russia because they will be getting 60 to 70% of their energy from Russia and a new pipeline.
You tell me if that’s appropriate because I think it’s not. On top of that Germany is just paying just a little bit over 1% whereas the United States is paying 4.2% of a much larger GDP. So I think that’s inappropriate also."
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