PM to give No 10 speech over Greenland rowGetty ImagesThe prime minister will take to the Downing Street lectern this morning, after another extraordinary weekend of diplomatic turmoil prompted by US President Donald Trump. Sir Keir Starmer knows that people and businesses in the UK will expect him to respond, in front of the cameras, to the prospect of the UK and European allies being hammered by more US tariffs. It is the latest twist in the row over Greenland, the autonomous Danish territory Trump wants to get his hands on. Trump has said he will impose new taxes on eight US allies - Denmark, Finland, France, Germany, the Netherlands, Norway, Sweden and the UK - on 1 February if they continue to oppose his proposed takeover of Greenland. Starmer holds phone call with Trump over Greenland tariff threat'Europe won't be blackmailed,' Danish PM says in wake of Trump Greenland threatsEU weighs response to Trump's tariff threat over GreenlandOne long-standing observer of Western diplomacy told me: "This is extraordinary. We haven't seen anything like this in 80 years. "This is pure political coercion against Nato allies over the attempted seizing of a chunk of territory - it's astonishing."Expect Sir Keir to reiterate that he believes the imposition of tariffs would be a mistake, and make clear that is something he spelt out directly to Trump on the phone on Sunday. Downing Street said Sir Keir spoke to the Danish prime minister, the president of the European Commission and the Nato secretary general on Sunday, before calling Trump. Labour insiders, well aware this is another blast of turbulence they could frankly do without, argue the capacity of the UK to be central to these diplomatic conversations is down to their "reset" with the EU and their establishing a strong relationship, despite obvious political differences, with the Trump administration. But when pressed on what might happen next, or what the next move from European allies might be, there is, from some, a shrug of the shoulders.