Novo Nordisk shares fell as much as 6.4% in early trading Friday after U.S. President Donald Trump signaled the price of the Danish drugmaker's weight-loss drugs would be lowered.

Since taking office in January, Trump has been striving to narrow the gap between U.S. and foreign drug prices.

Under its "most favored nation" policy, the U.S. government will require drugmakers to charge patients in the U.S. no more than in other wealthy nations.

Trump made the comments during a White House event on fertility treatments and drug pricing. He was asked by reporters to identify the drug that he earlier in the event said would be made less expensive.

"I was referring to Ozempic, or — I was referring to - the fat loss drug?.... They'll be much lower," Trump said.

Although Novo's Ozempic is approved to treat diabetes, it shares the same active ingredient as the group's blockbuster weight-loss drug Wegovy.

In the United States, Ozempic has been frequently used as a so-called off-label treatment for obesity and often served as a generic reference to weight-loss drugs. UBS analysts said they had already factored potential U.S. price cuts into their forecasts.

"If the prices mentioned by President Trump end up being the negotiated prices then this would be more than captured by our numbers," they wrote. Novo's shares fell to a near three-week low of 342.3 crowns and were last down 6.3% at 343 crowns.

Shares in rivals Eli Lilly and Zealand Pharma were down around 4% and 6%, respectively. A Novo spokesperson said the company was in discussions with the Trump administration over the most favored nation order.