Tens of thousands of demonstrators gathered here Saturday in the US capital in support of President Donald Trump who has not yet conceded to Democrat President-elect Joe Biden in the Nov. 3 presidential election.

Supporters flocked to Freedom Plaza earlier in the day, about one block from the White House, which has been a focal point for most demonstrations.

Protestors carried banners that read: "Two term Trump," "We support you Mr. President" and "We the people are pissed!" and chanted "Stop the steal" and "Four more years."

Several groups marched under the "Million MAGA March," "The March for Trump" and "Stop the Steal DC" rallies.

The outgoing president tweeted Friday that he may make an appearance at the rally. Saturday morning his motorcade drive near the rally, cheering Trump demonstrators who claimed Trump had won the election.

Trump is challenging election results and claims electoral fraud and irregularities but authorities have said the 2020 elections were the most secure in history.

White House spokeswoman Kayleigh McEnany claimed there were 1 million marchers.

"Best base in political history — we LOVE you guys!!!" she tweeted.

Trump also took to Twitter to claim hundreds of thousands of people showed support in the US capital.

"They will not stand for a Rigged and Corrupt Election!" he wrote.

Biden has 290 electoral votes, surpassing the 270 needed to claim victory in the presidential elections.

The president-elect will be sworn into office in January.