President Donald Trump claimed victory in the US presidential election and suggested Democrats were committing fraud as key states continued to count hundreds of thousands of mail-in ballots.

“Millions and millions of people voted for us today,” he said, “and a very sad group of people is trying to disenfranchise that group of people, and we won’t stand for it.

“This is a fraud on the American public. This is an embarrassment to this country. We were getting ready to win this election. Frankly, we did win this election,” President Trump said in remarks from the White House.

“This is a major fraud on our nation,” Trump said.

Trump claimed he is winning in key states – Pennsylvania, Michigan, and Wisconsin – that have just begun to count mail-in ballots likely to favour Democratic presidential candidate Joe Biden.

Speaking in Wilmington, Delaware, a couple of hours earlier, Biden called for “patience” while the counting of ballots continued.

“It ain’t over ‘til every vote is counted, every ballot is counted,” Biden said.

“It’s not my place, or Donald Trump’s place, to declare who’s won this election. That’s the decision of the American people,” Biden said.

Trump has won most of the Republican-leaning states he was expected to win and claimed he is winning in North Carolina and Georgia where votes are still being counted.

“It’s also clear that we have won Georgia,” Trump said. “They are never going to catch us. They can’t catch us.”

Trump said he plans to challenge the continuing counts of mail ballots in the US Supreme Court, although the legal grounds he will claim are not clear.

“We will be going to the Supreme Court. We want all voting to stop. We don’t want them to find any ballots at 4 am in the morning,” Trump said.

Biden campaign manager Jen O’Malley Dillon said in a statement: “The president’s statement tonight about trying to shut down the counting of duly cast ballots was outrageous, unprecedented, and incorrect.”

“The counting will not stop. It will continue until every duly cast vote is counted. Because that is what our laws – the laws that protect every Americans’ constitutional right to vote – require,” O’Malley Dillon said.

The Associated Press issued a bulletin saying it is not calling the presidential race yet, despite President Donald Trump’s claims of victory, because neither candidate has secured the 270 electoral college votes needed to win.

“His assertion of victory does not match the results and information currently available to the AP,” the news service reported.

Several key states are too early to call, including Pennsylvania, Georgia and Michigan, the AP said.

Pennsylvania’s Attorney General Josh Shapiro tweeted the proper count would take time.

“We knew this was going to go long… into tomorrow morning and maybe even longer but look, we feel good about where we are. We believe we are on track to win this election,” Biden said.

“Because of the unprecedented early vote, it’s going to take a while. We’re going to have to be patient,” Biden said.

“We are feeling good. We are feeling good about where we are,” Biden said.

“We are confident about Arizona. That’s a turnaround. We’re also just calling for Minnesota and we are still in the game in Georgia, although that’s not what we expected. And we are feeling really good about Wisconsin and Michigan. And by the way it’s gonna take time to count those. We are going to win in Pennsylvania,” Biden said.

“I am optimistic about this outcome,” Biden said. “Keep the faith guys, we are going to win this.”