INDIANAPOLIS:  US President-elect Donald Trump on Thursday warned American firms wanting to relocate abroad that they will face punishment, as he announced a deal with air conditioning manufacturer Carrier to keep jobs in the country.

"Companies are not going to leave the United States any more without consequences. Not going to happen," Trump told workers at the Carrier plant in Indianapolis in his first major public remarks since winning the White House.

"They can leave from state to state, and negotiate deals with different states, but leaving the country will be very, very difficult," Trump added. During the presidential campaign, the Republican billionaire threatened to slap tariffs on firms that decamped for places like Mexico or Asia where labor costs are cheaper. It became a repeated refrain of his victorious campaign.

Trump specifically singled out Carrier, a brand of United Technologies Corporation, saying he had been encouraging the company not to shift thousands of jobs to Mexico. If they did, he said his administration would impose major tariffs on Carrier products as they made their way back into the United States.

"But I called Greg (Hayes, UTC's chairman) and I said it's really important, we have to do something because you have a lot of people leaving and you have to understand we can't allow this to happen anymore with our country,"

Trump said as he recalled an early exchange with the firm's top executive. Under a deal hammered out with the help of Vice President-elect Mike  Pence, who is Indiana's outgoing governor, the state offered Carrier $7 million in incentives over 10 years, "contingent upon factors including employment, job retention and capital investment," the company said in a statement.

Pence said the deal will keep about 1,100 jobs in "the heart of the heartland."

"This is a great day for Indiana and it's a great day for working people all across the United States of America," Pence said. The deal is seen as an extraordinary industry intervention by a president-elect. His supporters have described it as the first tangible part of  Trump's jobs creation plan.

But liberal Senator Bernie Sanders, who challenged Hillary Clinton for the 2016 Democratic presidential nomination, said the deal should worry Americans. Carrier "took Trump hostage and won," Sanders said in an op-ed he wrote for The Washington Post.

Trump "endangered" other US jobs, Sanders said, "because he has signalled to every corporation in America that they can threaten to offshore jobs in exchange for business-friendly tax benefits and incentives." -APP