Prosecutors in Mexico say that Karime Macías, the wife of disgraced Mexican politician Javier Duarte, is being held in London.
Mexico has requested the extradition of Ms Macías, 43, who reportedly lived in luxury in the British capital.
Her husband, the former governor of Veracruz province, is serving a nine-year sentence in jail for corruption.
Mr Duarte was dubbed “the worst governor in history” after he pleaded guilty to embezzling public funds.
‘Privileged London life’
Ms Macías is also suspected of having embezzled public funds and Mexican officials had requested a year ago that she be extradited to her home country.
Her lawyer, Marco Antonio del Toro, said that she had handed herself in voluntarily. Mr del Toro also said that his client had requested political asylum in the UK “following rights abuses committed since Javier Duarte was arrested”.
Javier Duarte later confirmed in an interview that his wife was residing in London with their three children.