Updated, 5:15 p.m.:

After backing out of a Sept. 30 debate scheduled to be hosted by WFAA-TV in Dallas, Greg Abbott's campaign announced Friday afternoon that it has accepted an offer for Abbott to appear at a Dallas debate, on the same date, to be hosted by KERA, NBC5/KXAS-TV, Telemundo 39 and The Dallas Morning News.

Updated Aug. 29 at 11:35 a.m.:

Democratic gubernatorial candidate Wendy Davis' spokesman Zac Petkanas issued a statement after Greg Abbott, her Republican opponent, pulled out of the only televised statewide debate:

"It's no surprise that Greg Abbott is pulling out of a long planned debate the day after he was defeated in court for protecting billions in public education cuts that have led to overcrowded classrooms, teacher layoffs and shuttered schools," Petkanas said. "Greg Abbott is clearly too afraid to defend his record of siding with insiders at the expense of Texans -- whether it's defending funding cuts for classrooms, siding with a corporation against a victim of rape or letting his donors take tens of millions of taxpayer dollars intended for cancer research. This is nothing short of an insult to the voters of Texas."

Original story:

DALLAS — Republican candidate Greg Abbott has reversed his decision to appear in the only gubernatorial debate scheduled to be broadcast statewide on television.

Abbott and his Democratic opponent, Wendy Davis, had both agreed to participate in a Sept. 30 roundtable debate in Dallas.

But on Friday morning, Abbott's team said it would not participate, expressing concern over the format.

"Due to our inability to agree on specific details of the format, Attorney General Greg Abbott will regretfully not be participating in the WFAA debate," Robert Black, a senior campaign adviser said Friday morning.

Black, Abbott's new debate consultant, joined the campaign on Aug. 4.

On May 28, Wayne Hamilton, Abbott's campaign manager, sent a letter to WFAA accepting the terms of the debate.

"From grassroots events to policy announcements and roundtable discussions, we have made our personal engagement with voters a focal point," Hamilton wrote to WFAA in May.

"We are deeply disappointed that the Abbott campaign has not lived up to the commitment it made to participate in this important debate," said Mike Devlin, president and general manager of WFAA-TV. "WFAA has produced numerous debates which are balanced and fair to all the candidates. This debate would be no different. The citizens of Texas deserve to hear from the candidates for the most important office in the state."

Roundtable debates don't formally time responses for candidate answers. The looser format is designed to create a conversation and give voters a more candid look at candidates and their positions. Among the moderators scheduled to take part in the debate was Texas Tribune Executive Editor Ross Ramsey.

The Dallas debate was scheduled for 7 p.m. on Sept. 30 and would have been broadcast on all of Texas' Gannett stations including WFAA-TV in Dallas – Fort Worth, KHOU-TV in Houston, KENS-TV in San Antonio, KVUE-TV in Austin, along with other affiliates in Amarillo, Beaumont, Corpus Christi, San Angelo and Tyler.

The debate was also going to be available to any radio and television station in the state. In addition, the debate would have been streamed online on several sites.

Currently Abbott and Davis are only scheduled to appear together in one debate in McAllen on Sept. 19.

Davis originally requested multiple debates statewide but Abbott said he would only do two – one in McAllen and the one in Dallas.

Jason Whitely is a senior news reporter at WFAA-TV and host of Inside Texas Politics. He can be reached at jwhitely@wfaa.com.