Mexican President Enrique Pena Nieto says he will ask Congress to raise the limit on decriminalized marijuana for personal use to 28 grams, or about one ounce.

Mexico had previously exempted from prosecution only five grams, or less than a fifth of an ounce.

Pena Nieto's proposal also would allow the use and importation of cannabis-based medications.

The bill presented Thursday would allow freedom for people who are on trial or serving time for possession of up to an ounce of marijuana.

The move comes after Mexico's Supreme Court approved an appeal by four people to allow them to grow and possess marijuana for personal use.

The ruling launched a national debate on marijuana policy.