Raleigh, N.C. — State Republican leaders discussed a half-million dollar loan given to former House Speaker Jim Black.

Last week, prosecutors revealed the money came from an unnamed lobbyist in 2000. On Tuesday, state GOP leaders asked the lobbyist to come forward.

"This most recent revelation about former Speaker Jim Black further illustrates the complete breakdown of ethical standards during his term as one of the most powerful political officials in North Carolina government,” said Sen. Phil Berger (R-Rockingham). "Not only was it unethical for Mr. Black to solicit this money, but it was equally as deceitful for a lobbyist to write the check and give it to Black. Anyone with knowledge, including the lobbyist, should come forward. "

"The people of North Carolina have a right to know more about this $500,000 deal. There is clearly much more to be done to show that legislative Democrats understand the necessity of restoring our state’s reputation for honest government," Berger said.

Berger, along with State Rep. Paul Stam (R-Wake), called for the State Board of Elections and legislative Democrats to move forward with a formal investigation.

Black's attorneys said there was nothing unlawful about the loan, but investigators are still looking into it.

The 72-year-old Mecklenburg County Democrat  was sentenced July 11 to 63 months in prison and three years on probation for accepting more than $25,000 in cash from chiropractors while backing legislation favorable to the industry.

Black is set to start his five-year prison sentence for a federal corruption charge on July 30. However, Black's attorneys want to push back that date to Sept.10.

Black's attorneys made the request so he could attend doctor's appointments and his sentencing on state charges scheduled for 9:30 a.m. on July 31.