Mexico's president has lashed out at Moody’s ratings service after it downgraded the Mexican government’s debt outlook to “negative.”

Moody's linked Mexico's credit outlook downgrade to the nation's government debt and the constitutional overhaul of its judiciary system.

Mexico's outlook was moved to negative from stable by Moody's Ratings on Thursday, as the major credit rating agency pointed to institutional and policy weakening that risks undermining the economy as well as government accounts.