By Julian Miglierini
BBC News, Mexico City
The decision not to show the episode sparked criticism and derision
A last-minute decision by MTV in Mexico not to broadcast an episode of the US cartoon show South Park has caused controversy.
The episode portrays Mexico's president as a leader who wastes funds and irritates the international community.
MTV Mexico said they did not get a special permit needed to broadcast an image of Mexico's flag, seen briefly in the same scene as the president.
But Mexican South Park fans reacted with scepticism to that explanation.
The episode was to have been shown in Spanish on Monday night on MTV's Latin American channel.
"Has it been censored by the Mexican government?" wonders a blogger at the popular MexaBlog, while comments on other websites ridiculed MTV's decision.
The Mexican president in the episode is said to resemble Felipe Calderon
A spokesman for MTV Mexico reassured the BBC that the reason the episode was not shown was that the permit required to show the flag did not arrive in time for the scheduled broadcast.
The episode, called "Pinewood Derby", attracted keen interest from Mexican media when it was first shown in the US in 2009.
It features the character of a Mexican president with a striking resemblance to the incumbent, Felipe Calderon.
MTV Mexico had extensively publicised the broadcast of the Spanish-language episode.
But at 2200 local time on Monday night, Mexican TV viewers could only see another episode of the series.
Erick Zermeno, spokesperson for MTV Mexico, said that they had decided to pull the entire episode instead of trying to cover the flag artificially to avoid a possible fine from the government.
"We decided not to alter the image because the reaction would have been worse," he said.
Mr Zermeno told the BBC that as soon as the permit was ready the episode would be broadcast in its entirety and without alterations.
Mexico has strict regulations regarding the use of its flag and the broadcast of its image.
This is not the first time the use of the flag in the entertainment industry has generated a storm.
In 2008, Mexican pop singer Paulina Rubio was fined for posing nude wrapped in the Mexican flag in a photo shoot for a Spanish magazine.