U.S. President Donald Trump on Friday pitched a national project to accelerate the development of a coronavirus vaccine, saying he hopes for results by the "end of the year" or "maybe before."

Experts have identified the 14 most promising vaccine candidates and will work to narrow the list, Trump said, adding that the government will invest in manufacturing all of the top candidates prior to their regulatory approval under what he calls "Operation Warp Speed."

"Typically pharmaceutical companies wait to manufacture a vaccine until it has received all of the regulatory approvals necessary. And this can delay (the) vaccine's availability to the public as much as a year and even more than that," he explained.

(U.S. President Donald Trump speaks during a press briefing about coronavirus testing in the Rose Garden of the White House on May 11, 2020 in Washington, DC.)

The operation's objective is to therefore "finish developing and then to manufacture and distribute a proven coronavirus vaccine as fast as possible," Trump said at a press conference. Experts say vaccine development will likely take 12 to 18 months, or longer.

He also said the United States is working with other countries and would welcome the achievement if others develop a vaccine first.

"We have no ego. Whoever gets it, we think it's great. We're going to work with them, they're going to work with us," Trump said, noting that he believes the United States will have access to a vaccine even if it is developed by China, which he has accused of failing to stop the spread of the novel coronavirus at an early stage.

Trump, meanwhile, said he will push for states across the country to reopen their economies following coronavirus-triggered shutdowns regardless of the existence of a vaccine.

"I just want to make something clear. It's very important -- vaccine or no vaccine, we're back," said the president, who is hoping to put the economy back on track ahead of the November election.

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