US filmmaker Oliver Stone blasted outgoing Mexican President Felipe Calderon as a "disaster", saying he had plunged his country into a "nightmare" by declaring war on drug cartels.

Speaking in Beverly Hills as he presented his latest film "Savages" -- which tells the story of the deadly struggle between Californian cannabis producers and a Mexican cartel -- the controversial director didn't mince his words.

"Calderon is a disaster. He was equivalent to George Bush," the 65-year-old director said, referring to former US president George W. Bush.

"It's a shame because he brought what George Bush brought to this country, he brought a nightmare to Mexico by declaring war on these guys. Four cartels became seven cartels and there is more violence. It's like a civil war."

Calderon was elected in 2006. His war against drug traffickers, spearheaded by the army, has since left over 50,000 people dead, including many civilians.

Stone alleged that Calderon cheated his way into power six years ago over leftist candidate Andres Manuel Lopez Obrador, who lost by less than one percentage point.

"He did steal the election. I have no doubt that Obrador won," he said.

The Mexican leader is due to stand down after his country's presidential election on July 1.

The latest polls show the race tightening, with frontrunner Enrique Pena Nieto centrist Institutional Revolutionary Party (PRI) just four points ahead of Lopez Obrador, who is running again for the top leadership post.

Trailing in third place is Josefina Vazquez Mota of Calderon's center-right National Action Party (PAN).

"I hope the new party guy is much more pragmatic and gets down to decriminalizing drugs with the US," said Stone, whose latest film comes out in North America on July 6.