President Donald Trump said early Wednesday that large-scale oil, gas and mineral exploration is about to begin in Greenland, Fox News reported.

"Massive Oil, Gas, and Mineral Exploration is getting ready to begin in our new and beautiful Greenland!" Trump wrote on Truth Social, according to Fox News. He did not say when or how the work would start, the outlet reported.

In the same post, Trump said experts believe the amount of "easily available Oil" there is far greater than almost anywhere else in the world, both outlets reported. He also pointed to the island's value for defense. "Any future attack on the United States will have to come across Greenland," he wrote, CNN reported.

Greenland's government quickly pushed back. Jørgen Hammeken-Holm, the territory's deputy mining minister, said there are "activities by US companies," CNN reported. But he told CNN that "we are very far away from 'massive' exploration."

"There are many smaller explorations underway but these could take years to become operational," Hammeken-Holm added, according to CNN.

Greenland is a self-governing part of Denmark, and it controls its own mineral resources, Fox News reported. It stopped giving out new oil and gas licenses in 2021 because of climate concerns, the outlet said. Some older licenses are still valid. But drilling still needs more approvals.

About 80% of the island is covered in ice, CNN reported. Many of its deposits sit in remote places with few roads or ports.

Trump's post came weeks after the United States, Denmark and Greenland signed a new security agreement, both outlets reported. The deal gives the U.S. military more access to the island, but it does not make Greenland part of the United States, Fox News said. It mentions "minerals cooperation" but says nothing about oil or gas, according to CNN.

What we know: Trump says major exploration is about to begin, and Greenland's deputy mining minister says that is years away.
What we don't: Which companies or projects Trump was referring to.