President-elect Donald Trump has suggested that millions of people voted illegally in the November 8 US presidential election.
In a tweet on Sunday, Mr Trump said he won the election "if you deduct the millions of people who voted illegally", but provided no evidence of widespread voter fraud.
Mr Trump also alleged that there had been "serious voter fraud" in Virginia, New Hampshire and California, and claimed the media was not reporting on it because of "serious bias".
In a series of other tweets, the Republican politician added: "It would have been much easier for me to win the so-called popular vote than in the Electoral College in that I would only campaign in 3 or 4 states instead of the 15 states that I visited."
Mr Trump's allegation comes as his Democratic former presidential rival Hillary Clinton's lead in the popular vote exceeded two million votes, and is expected to grow to more than 2.5 million as ballots in populous states such as California continue to be tallied.
Mrs Clinton's legal team said it has agreed to take part in a recount of votes in Wisconsin after the state's election board approved a request by Green Party candidate Jill Stein.
In a tweet on Saturday, Mr Trump dismissed a fundraising effort by Ms Stein to launch recounts in Wisconsin, Michigan and Pennsylvania as a "scam".
Before the election, Mr Trump made a number of unsubstantiated allegations that the results of the election might be rigged against him.
However, several studies have found no evidence of widespread or significant voter fraud.
Barack Obama's administration has said there is no evidence of electoral tampering, but experts have maintained that the only way to verify that the results are accurate is to conduct a recount.