Nikki Haley, Lindsey Graham Will Call for Removal of Confederate Flag, Sources Say

South Carolina Gov. Nikki Haley and Republican senators Lindsey Graham and Tim Scott plan to call for the removal of the Confederate battle flag from the grounds of the state Capitol, sources told NBC News on Monday.

Both South Carolina senators plan to join Haley at a 4 p.m. news conference, sources told NBC News. While Haley was campaigning for re-election last year, she said there was no need to take down the flag.

Meanwhile, political and religious leaders in the state urged lawmakers to vote to remove the flag as early as Tuesday in tribute to the nine people gunned down at a historic black church in Charleston last week. Authorities have said the shooting was a hate crime, and a white supremacist website that may be linked to shooter Dylann Roof shows images that apparently show him holding the flag.

"This act will do something very personal," Charleston Mayor Joe Riley said on Monday.

"Take away Mr. Roof's symbol of misguided idea of racial superiority and bigotry. Take it away from him and all like him and give the front of our state Capitol equally and fairly to every citizen of South Carolina," he said.

U.S. Sen. Lindsey Graham and South Carolina Gov. Nikki Haley before a deployment ceremony at Ft. Jackson, S.C., in 2013. Rainier Ehrhardt / AP file

Rev. Nelson B. Rivers III, a National Action Network and NAACP official, called for the flag to come down before Rev. Clementa C. Pinckney, who was a state senator, lies in state on Wednesday. He was the pastor of Emanuel AME and one of the nine victims of Wednesday's shooting.

"We should not go another week with that symbol of hate that was adored by the man who killed them to sit in front of the people's house," Rivers said.

Related: Mitt Romney Joins Call for Confederate Flag to Come Down After Shooting

The leaders, also including Chairman of the Charleston County Council J. Elliott Summey, Senator Marlon Kimpson (D-Charleston), North Charleston Mayor Keith Summey and National Action Network state President Elder James Johnson, also called for residents to meet in front of the Statehouse Tuesday to urge the General Assembly to vote to take the flag down.

The flag wasn't lowered to half-staff after the shooting along with the other flags at the Statehouse because doing so is under the authority of the state's General Assembly — and so is taking it down.

The General Assembly's session ended on June 4, but lawmakers are meeting Tuesday to pass a budget compromise, at which point they can vote on extending the session to debate the Confederate flag. A decision to continue the session would take two-thirds of the vote, as would passing legislation to take down the flag.