Weeks ahead of his second inauguration, U.S. president-elect Donald Trump again threatened the country's trading partners with new tariffs unless they buy more oil and gas from America.

"I told the European Union that they must make up their tremendous deficit with the United States by the large scale purchase of our oil and gas," the former president said in a Truth Social post around 1 a.m. ET Friday. "Otherwise, it is TARIFFS all the way!!!"

Trump made tariffs on other countries a key piece of his campaign platform. Since winning last month's election, Trump has said he wants to place a 25% tariff on all imports from Mexico and Canada, along with a 10% additional tax on goods from China.

The U.S. had a trade deficit of $131.3 billion with the E.U. in 2022, according to the U.S. Trade Representative.

E.U. representatives have said they are working on solutions to decreasing energy imports from Russia, and oil and gas from the U.S. could be an option, according to CNBC. Former Italian Prime Minister Enrico Letta told CNBC Friday that it is "incorrect" to connect oil and gas imports to tariffs on other goods, as they are "completely different" topics.

E.U. officials have said they are more prepared to handle a Trump term and the trade conflicts it could bring than they were in 2017, and are prepared to maintain a "Europe United" policy in response to Trump's likely "America First," Bloomberg reported.

Separately late Thursday, regulatory filings showed that Trump has transferred all of his shares in Trump Media and Technology Group (DJT) to a revocable trust with his son Donald Jr. as the sole trustee. Trump transferred some assets to the same or similar trusts ahead of his first term in 2017, according to CNBC.