A British grandmother has lost her appeal and will now be executed in the US for arranging for three men to abduct and kill a mother and kidnap the victim's four-day-old son so she could pass him off as her own.

The Texas Court of Criminal Appeals Wednesday upheld the ruling of a lower court, which rejected Linda Carty's claims that prosecutors had coerced witnesses and hidden evidence.

Carty, 59, a native of St. Kitts and Nevis and the only British woman on death row in the United States, was convicted in the 2001 suffocation of 20-year-old Joana Rodriguez.

Prosecutors said Carty, who had been living in Houston for about 20 years by the time of her trial, recruited three men to abduct Rodriguez and her newborn son, Ray Cabrera, in the hopes of saving her relationship with her common-law husband by passing off the child as her own. She had previously suffered several miscarriages.

Death-row inmate Linda Carty poses for a photo at the Texas Department of Criminal Justice Mountain View Unit outside Gatesville, Texas. She was convicted of murdering Joana Rodriguez

Victim: Rodriguez, 20, was kidnapped and murdered by three men in 2001

Carty, a former primary school teacher, was convicted under the Texas 'law of parties' which dictates that a person is criminally liable if one 'solicits, encourages, directs, aids, or attempts to aid the other person to commit the offence'.

She has maintained her innocence arguing that she was convicted largely on the word of her co-accused.

Rodriguez and Ray were abducted from their Houston apartment on May 16, 2001.

Prosecutors said Carty (pictured before she was jailed) had been living in Houston for about 20 years by the time of her trial

The boy was found safe in a car that same day, but his mother was found suffocated in the trunk of another car.

Her arms and legs were wrapped in duct tape, her mouth and nose were also taped and she had a plastic bag over her head.

Gerald Anderson, Chris Robinson and Carlos Williams were charged as Carty's accomplices and received long prison terms. Carty was sentenced to death.

Carty's lawyer, Michael Goldberg, said Wednesday that he was unaware of the ruling and had no immediate comment.

The appeals court ruling supported the findings of District Judge David Garner, who decided in 2016 that Harris County prosecutors should have turned over some witness statements to Carty's trial lawyers, but that the evidence was overwhelming and wouldn't have changed the trial's outcome.

Garner also determined that prosecutors didn't knowingly use perjured testimony or allow untrue testimony at the trial.

In a concurring opinion joined by two other appeals court judges, Judge Bert Richardson wrote that while Carty's lawyers contended that prosecutors committed 'egregious misconduct', those claims weren't supported in the court record.

'None of the evidence eliminates her or even casts reasonable doubt on her role as a party to this offense,' Richardson wrote.

When she was arrested, Carty was on probation for impersonating a federal agent and previously had been arrested for auto theft and drug charges.

Her daughter Jovelle Carty, who lives in Houston according to social media, has been rallying support from politicians in the UK to stop her execution.

Linda Carty talks from behind the glass as part of a documentary into her sentencing in the US

Locked-up: Carty (left) speaks from behind bars in the Harris County Jail back in 2004. Her daughter Jovelle Carty (right) has been rallying support from politicians in the UK to stop her execution

Support: Human rights campaigner Bianca Jagger poses for photographers in a mock prison cell in London on September 7, 2010

The British Foreign Office has supported her cause and her case has received celebrity backing from Bianca Jagger - Mick Jagger's ex-wife - and the support of campaigners at the human rights organisation Reprieve.

In 2009 campaigner Brian Capaloff held a placard beside a cardboard cut-out picture of Carty while standing on the fourth plinth in Trafalgar Square in London on September 10. Capaloff used his one-hour slot on the plinth to highlight Carty's case.

Carty has been the subject of documentaries and spoke to Sky News from behind bars in Huntsville Prison, Texas, in 2012 where she claimed she was: '110 percent innocent'.

Brian Capaloff (L) holds a placard beside a cardboard cut-out picture of Linda Carty while standing on the fourth plinth in Trafalgar Square in London on September 10, 2009. Capaloff used his one-hour slot on the plinth to highlight Carty's legal case

She maintained that she was framed for the crime in the interview saying she felt for the victim's family.

She said: 'She's somebody's child too and she's somebody's daughter. So for me it's not only a healing process for me but to show the families that the person you have been hating all these years and that you thought because the state of Texas told you this is who did it, did not commit this crime.'

She does not yet have an execution date. She would become the first female British to be executed since 1955.

Ruth Ellis was hanged for shooting her lover outside a pub in North London.