The European Central Bank has cautioned against United States President Donald Trump interfering with the US Federal Reserve, saying any undermining of its independence would present a "very serious danger" to the world economy.

The European Central Bank, or ECB, is the central bank for the 20 European nations that use the euro for currency.

Christine Lagarde, the ECB's president, said there would be "very worrying" consequences if the US Federal Reserve, or Fed, which is the US' central bank, took its orders from Trump instead of continuing to act at arms-length of Washington to best promote employment, keep prices stable, and ensure the health of the US economy.

"I think it would be a very serious danger for the US economy and the global economy if that policy wasn't independent anymore, if it was dependent on the political dictates of one person or another, then the balance of the US economy and consequently the impacts that has on the world as a whole, because it is the world's largest economy, would be very worrying," she told the French radio station Radio Classique on Monday.

Lagarde made the comment after Trump tried last month to fire one of the Fed's governors, and following his repeated criticism of the Fed's chairman, Jerome Powell, who Trump has described as a "numbskull".

But Lagarde said the Fed, which uses interest rates to influence the US economy, is relatively well insulated from Trump's interference, even though it will have heard his repeated calls for interest rates to be lowered.

Lagarde, who is a former head of the International Monetary Fund, said the US Supreme Court has made it clear the Fed's governors can only be dismissed if they have been found guilty of gross misconduct.

Ray Dalio, the founder of asset management company Bridgewater Associates, echoed Lagarde's concerns, telling the Financial Times newspaper a politically compromised US central bank "would undermine the confidence in the Fed defending the value of money and make holding dollar-denominated debt assets less attractive, which would weaken the monetary order as we know it".

The Fed's current target for its main interest rate is 4.25 percent to 4.5 percent but Trump has repeatedly said he wants to see it at less than 1 percent. The Fed has left the rate unchanged since December over fears a change would stoke inflation, and it has said it also needs to see how Trump's tariffs will affect the US economy.

US Treasury Secretary Scott Bessent seemed to try to calm worries on Monday, telling the Reuters news agency: "The Fed should be independent. The Fed is independent. But I also think that they've made a lot of mistakes."