Donald Trump says that preparations are underway to launch a "massive" oil, gas ‌and mineral exploration in Greenland.

In a post on Truth Social, the US president wrote: "Massive Oil, Gas, and Mineral Exploration is getting ready to begin in our new and beautiful Greenland!"

Mr Trump continued: "There are ‌experts that are saying that the amount of easily ​available oil is far greater than that of almost any land, anywhere in the ​world".

He did not share details about the exploration plans in Greenland, which is a semi-autonomous territory of Denmark.

His announcement comes a month after the US, Denmark ⁠and Greenland signed an agreement aimed at ending tensions after the US president made repeated threats to take control of the strategically located and mineral-rich island.

Mr Trump re-emphasised this strategic importance on social media, adding that the island was "second to none" in security terms for both the US and Europe.

"Any future attack ‌on the United States will have to come across Greenland, where our Defense will routinely knock down drones, missiles, or any ⁠other form of weapon not ​yet even conceived," he wrote.

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The ​deal signed between the US, Denmark and ⁠Greenland expands the US military's role in Greenland and paves the way for two ⁠new military bases and ​Trump's "Golden Dome" missile defence system.

It also reaffirms Danish sovereignty and the Greenlanders' right to self-determination.

Mr Trump has repeatedly made his ambition to own Greenland known and has called on Denmark to sell the island, even making implicit threats of military action.

The shortest route between Russia and the US is over Greenland, making it a critical site for the US ballistic missile defence system.

It is already home to a large US military base, called the Pituffik Space Base.

Greenland also holds rich deposits of rare earth minerals needed for telecommunications, as well as uranium, and is estimated to have a vast supply of oil and natural gas that is becoming increasingly accessible.