Sir Keir Starmer is set to address the nation with an emergency press conference on Monday.
The Prime Minister is set to tell Britain of his commitment to protecting their security, standards of living and future.
Sir Keir is expected to set out how Britain will work alongside its allies and how the country will be “led by our values”.
The emergency press conference comes amid a rift between Europe and the US over President Donald Trump's threats to enforce tariffs until a deal is reached over the sale of Greenland.
On Sunday, the Prime Minister told Mr Trump that it was "wrong" to impose tariffs on Britain and other European countries who oppose his desire to secure control of the Arctic territory.
Sir Keir also held talks with Danish Prime Minister Mette Frederiksen, EU chief President Ursula von der Leyen and Nato Secretary General Mark Rutte to restate Britain’s stance on Greenland.
European leaders said security in the High North remains a shared priority for Nato allies in defending wider Euro-Atlantic interests.
But on Monday morning, Donald Trump hit back with a fiery message to Denmark on social media.
"Nato has been telling Denmark for 20 years, that 'you have to get the Russian threat away from Greenland'. Unfortunately, Denmark has been unable to do anything about it," Mr Trump blasted.
"Now it is time, and it will be done!!!" he added.
The PM is set to address the nation on Monday morning
|PA
The President earlier said he would slap Britain with a 10 per cent tariff “on any and all goods” imported by the US from February 1, rising to 25 per cent on June 1.
The measures will also apply to Denmark, Norway, Germany, France and Sweden.
Mr Trump slammed the Danish-led military exercise carried out with European allies in Greenland this week, saying the countries involved “journeyed to Greenland, for purposes unknown”.
Britain's contribution to the mission was notably modest, with Defence Secretary John Healey confirming that just one officer had been dispatched to the Arctic island.
GREENLAND - READ THE LATEST:
Mr Trump slammed the Danish-led military exercise carried out with European allies in Greenland this week
| GETTYOn Sunday, a collection of European countries issued a joint statement addressing the President's tariff threats.
The message by Denmark, Finland, France, Germany, the Netherlands, Norway, Sweden and the UK read: "We stand in full solidarity with the Kingdom of Denmark and the people of Greenland.
"Tariff threats undermine transatlantic relations and risk a dangerous downward spiral.
"We will continue to stand united and coordinated in our response. We are committed to upholding our sovereignty.
Showdown in the High North: Why is Greenland strategically important? | GB NEWS"As members of Nato, we are committed to strengthening Arctic security as a shared transatlantic interest.
"The pre-coordinated Danish exercise 'Arctic Endurance' conducted with allies, responds to this necessity. It poses no threat to anyone."
Soon after the statement was released, Culture Secretary Lisa Nandy said Britain needed to engage in “adult debate” with the US, and alluded to the Trump administration being open to negotiation.
But she insisted that Britain's position remains that the future of the island is a matter for the people of Greenland and Denmark, telling the BBC: “That is non-negotiable. That is the starting point for the conversation."