Yingluck Shinawatra has been given a 10-year visa from the British government, according to BBC Thai.
“She can enter and leave England anytime but each stay in the kingdom must not exceed six months,” BBC Thai said in a Thai-language report, quoting a source.
The travel arrangements of the former prime minister since she left the country last year have been a subject of scrutiny in Thailand. Related agencies have told the public they are doing everything in their power to bring her back to serve time.
British officials refused to confirm the issuance of the visa, citing standard policy on privacy of personal information, according to the BBC Thai report.
It said standard terms of the 10-year non-immigrant visa provide that Ms Yingluck can travel freely in and out of the United Kingdom, but must return at least every six months.
Thai officials had earlier claimed that she held passports of Montenegro and Nicaragua, as had her brother Thaksin after his flight from Thailand.
Earlier, many speculated she might have claimed asylum in the UK.
Spokesperson Busadee Santipitaks confirmed that the British government had provided no information about the visa application to the Thai government. She said the Ministry of Foreign Affairs had no information about the BBC Thai report.
"[The MFA] only learned from the news report. The ministry itself has no information about this," she said.
The Foreign Ministry said it had already cancelled Ms Yingluck’s passports.
A long-term visa is better than an asylum in Yingluck's case since claiming the status usually takes a long time during which the applicant cannot go abroad, work or open bank accounts.
Yingluck left the country on Aug 24 of last year, the day before the Supreme Court was to issue its ruling on whether she was guilty of dereliction of duty over the rice policies of her government.
The following month, the court issued its ruling in absentia, finding that she had failed to stop fraud and corruption involving the rice-pledging policy and sentencing her to a 5-year jail term.
The spokeswoman was tight-lipped on Monday on a reported attempt to secure extradition of the former prime minister, Ms Busadee said: "The collaboration of agencies involved is ongoing," she said.