Hillary Clinton blasted Donald Trump for persisting for years with the "racist" questioning of whether President Obama was born in the United States. 

"He has really started his political activity based on this racist lie that our first black president was not an American citizen," she said, pointing out that Trump "persisted year after year" despite having no evidence for his claims.

She pointed out that Trump was sued in the 1970s for not renting properties to African-Americans.

"He has a long record of engaging in racist behavior," said Clinton, adding that Obama is "a man of great dignity" and was annoyed at the suggestion that he was not an American.

Trump, however, accused Clinton's 2008 presidential campaign of first raising the issue about Obama's birthplace. 

He alleged that Clinton's campaign manager sent a reporter to Kenya to investigate it and they "failed to get the birth certificate." 

Trump said he' "satisfied" for convincing Obama to release the document. 

Watch the exchange above.