WASHINGTON (Reuters) -U.S. President Donald Trump said on Wednesday he would be willing to extend a July 8 deadline for completing trade talks with countries before higher U.S. tariffs take effect, but did not believe that would be necessary.

Trump told reporters before a performance at the Kennedy Center that trade negotiations were continuing with some 15 countries, including South Korea, Japan and the European Union.

"We're rocking in terms of deals," he said. "We're dealing with quite a few countries and they all want to make a deal with us." He said he did not believe a deadline extension would be "a necessity."

Trump said the U.S. would send out letters in coming weeks specifying the terms of trade deals to dozens of other countries, which they could then embrace or reject.

"At a certain point, we're just going to send letters out ... saying, 'This is the deal. You can take it, or you can leave it,'" Trump said. "So at a certain point we'll do that. We're not quite ready."

U.S. Treasury Secretary Scott Bessent told lawmakers earlier that the Trump administration could extend the July trade deal deadline - or "roll the date forward" for countries negotiating in good faith, in certain cases.

A 90-day pause in Trump's broadest, "reciprocal" tariffs will end on July 8, with only one trade deal agreed with Britain and some 17 others at various stages of negotiation.

"It is highly likely that those countries - or trading blocs as is the case with the EU - who are negotiating in good faith, we will roll the date forward to continue the good-faith negotiations," Bessent told the House Ways and Means Committee. "If someone is not negotiating, then we will not."

Bessent's remarks marked the first time a Trump administration official has indicated some flexibility around the expiration date for the pause.

Bessent reiterated the possibility of more negotiating time at a second hearing before the Senate Appropriations Committee on Wednesday, saying it was "my belief that countries that are negotiating in good faith could be rolled forward."

He said the European Union had previously been slower to come forward with robust proposals, but was now showing "better faith," without providing specifics. Trump echoed that more upbeat view on Wednesday, saying, "They do want to negotiate."

A deal struck on Tuesday in London with China to de-escalate that bilateral trade war is proceeding on a separate track and timeline, with an August 10 deadline set last month.

The president has been the final decision-maker on his administration's tariff and trade policies, but Bessent's influence has increased in recent months and the Treasury chief has been viewed by many trading partners as a moderating voice.

Trump announced the pause on April 9, a week after unveiling "Liberation Day" tariffs against nearly all U.S. trading partners that proved to be so unexpectedly large and sweeping that it sent global financial markets into near panic.

The S&P 500 Index plunged more than 12% in four days for its heftiest run of losses since the onset of the COVID-19 pandemic in early 2020. Investors were so rattled they bailed out of safe-haven U.S. Treasury securities, sending bond yields rocketing higher. The dollar sank.

Markets started their recovery on April 9 when Trump unexpectedly announced the pause. The recovery continued in early May when the Trump team agreed to dial back the triple-digit tariff rates it had imposed on goods from China. Those events have given rise to what some on Wall Street have parodied as the "TACO" trade - an acronym for Trump Always Chickens Out.

"The only time the market has reacted positively is when the administration is in retreat from key policy areas," Democratic Representative Don Beyer of Virginia told Bessent before pressing him on what to expect when the July deadline expires.

"As I have said repeatedly there are 18 important trading partners. We are working toward deals with those," Bessent said before going on to signal a willingness to offer extensions to those negotiating in good faith.