"We've got nothing to hide": Andres Manuel Lopez Obrador said after the claim.

Mexican President Andres Manuel Lopez Obrador said Thursday a "sophisticated camera" had been found in his offices, but added that he was unconcerned because he has nothing to hide.

"A few days ago, in one of the rooms in the (presidential) offices, they found a sophisticated camera, one of those tiny little ones. We were being recorded," he told a news conference at the National Palace, the colonial building in central Mexico City where he lives and works.

Lopez Obrador, an anti-establishment leftist elected last year, did not indicate who could be behind the alleged espionage, but said he was not worried.

"What do they achieve by doing that? Everything we discuss is completely legal and transparent. There's nothing they could use against us," he said.

"I don't think it's a sensitive issue. We've got nothing to hide... Everything we say should be in the public domain."

Lopez Obrador is known for his laid-back approach to presidential security.

He dissolved the presidential guard upon taking office, relying instead on a small team of bodyguards, and mingles closely with crowds on his trips around the country -- which he criss-crosses on commercial flights, having also put the presidential jet up for sale.

"The people will protect me," he is fond of saying.