Texas Governor Rick Perry, a potential 2016 Republican presidential candidate, has been indicted over allegations he abused his power, prompting calls for him to resign.

A state grand jury in Austin indicted Perry on Friday on two felony charges – abuse of official capacity and coercion of a public servant – for his alleged threat to veto $US7.5 million ($A8.11 million) in state funding to an anti-corruption unit run by Travis County District Attorney Rosemary Lehmberg, a Democrat.

After Lehmberg was convicted of drunken driving, Perry said he would withhold the funding if she did not step down.

When Lehmberg refused to leave her office, Perry carried out his veto, but it is the apparent threat that has landed him in hot water.

Perry’s general counsel, Mary Anne Wiley, said: “The veto in question was made in accordance with the veto authority afforded to every governor under the Texas constitution.

“We will continue to aggressively defend the governor’s lawful and constitutional action, and believe we will ultimately prevail,” she added in a widely cited statement.

Lehmberg declined to comment on the indictment, which immediately triggered calls by rival Democrats for Perry to quit.

“We call on Governor Perry to immediately step down from office,” Texas Democratic Party chairman Gilberto Hinojosa said.

“Texans deserve real leadership and this is unbecoming of our governor.”

The Texans for Public Justice watchdog group, which filed a complaint in the case, said “the grand jury decided Perry’s bullying crossed the line into law breaking.

“Any gov under felony indictment should consider stepping aside,” it added in a tweet.

Perry, the longest-serving governor in Texas history, took office in 2000 and is due to end his term this year.

But the investigation and the indictment could ruin his chances for a 2016 White House bid, following his failed attempt in 2012.