Madrid: Tennis great Rafael Nadal has attacked a French satirical puppet show that implied he and other Spanish sports stars are drug cheats, saying it had crossed the line.

The sketches on Canal Plus France's television show "Les Guignols" whipped up a storm of outrage in Spain, prompting its foreign minister to order a formal protest to French media.

One sketch featured a puppet likeness of world number two Nadal refuelling the tank of his car from his own bladder, a fill-up which powers up the car and leads to him being pulled over by police.

In another, a satirical advert asks people to donate blood to cycling champion Alberto Contador, who has been slapped with a two-year doping ban, and thus share in the glory of his cycling victories.

The Les Guignols show is a "repeat offender", the 25-year-old tennis star told Spanish media on Thursday, adding that he had not seen the video himself.

"One day is ok but when, from what I understand, it is done repeatedly then that is not so good because it crosses the line a bit. And it is always with the same focus," he said.

"The institutions in general have to defend us because I don't think it is a campaign against me or a campaign against anyone. It is a campaign against Spain in general, and against Spanish sports."

Nadal said Canal Plus alone was not to blame.

"I don't think it is only Canal Plus that does it. I think there are other media pushing it along and I think that is something punishable because in Spain sportspeople who are not clean are punished, they don't compete."

"It is a globalized campaign from the neighbouring country," he said.

"With a lot less resources than them we have achieved much more in the last years so we are doing something better -- it is not a question of pills or syringes, I can assure you."

Nadal said Spain had a system of sports drugs testing that ensured cheats were excluded from competition. He added that he himself had been tested three times already this year.

The Swiss-based Court of Arbitration for Sport on Monday handed a two-year ban to Tour de France winner Contador after he tested positive for the banned substance clenbuterol.

Contador says it was due to a contaminated steak eaten during the 2010 Tour de France, one of three editions of the French race that he won. He said on Tuesday that his lawyers were looking into a possible appeal.

He posted a photo of himself on his official Twitter account on Friday riding his bike with the message: "Have returned to work. Sacrifice and hard training, that is the only secret".

The front page of top-selling Spanish sports daily Marca ran a drawing of Spain's sporting heroes including the World Cup winning football players with the headline: "They Are Not Puppets".

On Thursday, Foreign Minister Jose Manuel Garcia-Margallo said he had instructed the Spanish ambassador to France to send a written protest to French media including to Canal Plus.

Spain's tennis federation said the previous day it would sue Canal Plus for using its logo in the comedy sketches.

Canal Plus called the reactions "disproportionate", adding that Les Guignols is "a satirical programme that has poked fun at French and international current events for over 20 years."

A French foreign ministry spokesman said: "What is important is to calm spirits and to do this very quickly.

"Given that we are talking about criticism made of France about what can be said or done by French media, we recall that the press is independent," he added.