MEXICO CITY (Reuters) – The Mexican attorney general’s office said on Friday it had opened a criminal investigation into suspicions of illicit enrichment by former Economy Minister Ildefonso Guajardo, a senior official in the previous administration.

In a statement, the office said prosecutors believed Guajardo likely achieved an increase in his wealth during the 2014-2018 period that could not be legally accounted for.

Guajardo, who was in charge of renegotiating the North American Free Trade Agreement (NAFTA) spurred on by former US President Donald Trump, told Mexican radio he was being politically persecuted for having criticized the government.

A member of the Institutional Revolutionary Party (PRI), a centrist opposition party, Guajardo is expected to return to Congress when the new lower house meets in September.

A judge ordered Guajardo not to leave the country without judicial authorization and to report to authorities at regular intervals, the attorney general’s office said.

Guajardo said he was under investigation for around 9 million pesos ($ 452,265), specifically a painting he acquired, as well as a transfer of around $ 300,000 from his brother.

Speaking on the radio, Guajardo said he did not register the painting in his public declaration of heritage in the year he bought it because it had not yet been delivered.

President Andres Manuel Lopez Obrador has relentlessly sought to vilify the former Mexican administration, accusing it of fomenting inequality, corruption and violence in the country.

($ 1 = 19.8998 Mexican pesos)

(Reporting by Sharay Angulo and Raul Cortes; editing by Cynthia Osterman)