South Park episode pulled in Mexico | Gatton TV Guide | Gatton Television, Australia

MTV cancelled the Mexican broadcast of an episode of the South Park cartoon featuring President Felipe Calderon because it lacked permission to show the Mexican flag, a spokesman said.

The channel has now requested permission to show the flag, he added, following speculation that the widely-promoted episode had been censored by Mexican authorities after it failed to air on Monday.

"It merely wasn't broadcast for a legal reason. We saw that we needed special permission to use the flag," the spokesman from MTV Networks Mexico told AFP.

"We realised we needed to ask for permission and we're doing it," he added, saying that MTV expected to receive the green light to air the episode.

Under Mexican law, permission is required for the use of patriotic symbols such as the flag or national anthem. Violators face fines of up to $US5,000 ($A5,719).

Mexican singer Paulina Rubio was fined in 2007 for appearing in a Spanish magazine photograph wrapped in the Mexican flag.

The suspended episode of the irreverent show features a caricature of Calderon, portrayed as a spendthrift who wastes money on water parks, sitting in front of a Mexican flag.