Trump says the strikes are a "direct result" of Russia's failure to keep Syria's Assad from using chemical weapons RELATED: What the U.S. is doing in Syria The United States, along with assurance from France and the United Kingdom, launched a response Friday against the regime of Syrian leader Bashar al-Assad days after his government allegedly used chemical weapons on its citizens.

The remarks were another conciliatory signal from the administration following tit-for-tat tariffs proposals from the world's largest two economies that rattled markets.

Still, it's unclear to what extent the comments represent an actual shift in policy. While the United States would significantly bolster the pact if it signed up, its entry would require intense negotiations - and current members will expect significant concessions from the American side. But they also cautioned against making any significant changes.

An early test of the potential for the United States to rejoin could come as soon as next week, when Shinzo Abe, Japan's prime minister and an ardent champion of the pact, is to meet with Trump at his Mar-a-Lago resort in Palm Beach, Florida.

Trump had tweeted that the United States would only join TPP if the deal were substantially better than the deal offered to former president Barack Obama.

Toshimitsu Motegi, Japan's minister in charge of TPP, told Bloomberg it would be hard to change the deal, calling it a "balanced one, like fine glassware".

Trump "is a person who could change temperamentally, so he may say something different the next day", Aso said.

The S&P 500 Index closed up 0.8% and the Dow Jones Industrial Average added nearly 300 points, or 1.2%, as investors assessed the changing trade dynamics.

Trump withdrew the U.S. from the accord during his first week in office. Membership was negotiated by President Barack Obama but was never approved by Congress.

US President said the would only join the, a multinational trade pact his administration walked away from past year, if it offered "substantially better" terms than those provided under previous negotiations. AFL-CIO President Richard Trumka, head of the main trade union group, said on Twitter that TPP "was killed because it failed America's workers and it should remain dead". "You'd need a whole renegotiation".

Malaysia and members of the 11-nation Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) have jointly opposed any renegotiations to accommodate the United States should the country decide to participate in the trade deal.

"A combined operation with the armed forces of France and the United Kingdom is now under way", the president announced Friday night from the White House.

The U.S. left what was then a 12-nation pact in January 2017 during Trump's first full weekday in the Oval Office. "He's going to get rid of a lot of taxes and tariffs", Trump said of the Chinese leader.

US Commerce Secretary Wilbur Ross later said the administration needs to see concrete actions from China to reach a deal.