Prices of one of Mexico's main staple foods, the tortilla pancake, have risen by up to a third, after the lifting of government price controls on New Year's Day.

The Mexican trade ministry said the phasing out of subsidies would allow tortilla manufacturers to make more profit and invest in modern machinery.

Ground from corn and wheat, tortillas form the mainstay of the Mexican diet, much like bread in other countries, and correspondents say the price increases could lead to popular discontent.