WASHINGTON (Reuters) - President Donald Trump told chief executives of major U.S. companies on Thursday he plans to bring millions of jobs back to the United States, but offered no specific plan on how to reverse a decades-long decline in factory jobs. In his first month in office, Trump has pressured a number of U.S. companies to hire in the United States but he has yet to publicly propose legislation tackling the big economic issues he campaigned on in 2016, including a job-boosting tax or infrastructure program. He will address a joint session of Congress on Feb. 28. In a meeting with some two dozen CEOs at the White House, Trump said the United States had lost about one-third of manufacturing jobs since it joined the North American Free Trade Agreement in 1994 and asserted about 70,000 factories have closed since China joined the World Trade Organization 16 years ago.   But the Bureau of Labor Statistics says the number of private sector manufacturing facilities in the United States has fallen less than that, from nearly 400,000 in 2001 to 344,000 last year. Lower wages, automation, foreign competition and other factors account for the steep decline in manufacturing jobs, experts say.    Trump has promised to roll out proposals that he says could have favorable ramifications for companies, including a plan to overhaul the tax code and an infrastructure package that was part of his presidential campaign promises to create millions of jobs. He has declined to specify what he had in mind. “We’re going to find out how we bring more jobs back,” he told the CEOs.  General Electric Co (GE.N) chief executive Jeff Immelt said after the meeting in a Twitter post that “tax reform a high priority for job creation. Business community will come together to help find a workable solution.” Ken Frazier, CEO of Merck & Co (MRK.N), told reporters “it is very clear the president is interested in lessening the tax burden.” Several of the CEOs who met Trump are part of a coalition that supports a so-called border adjustment tax, which would impose a 20 percent tax on goods that are imported into the country while providing write-offs for goods that are exported.  In an interview with Reuters, Trump spoke favorably about the border adjustment tax proposal being pushed by Republicans in the U.S. Congress, but did not specifically endorse it.  Trump is scheduled to dine at a Washington hotel on Thursday evening with members of The Business Council, a group of major U.S. company CEOs, including Immelt, Goldman Sachs’ Lloyd Blankfein and JP Morgan Chase’s Jamie Dimon. 