President Garcia cancelled planned talks with Chile's Michelle Bachelet
A new diplomatic row has erupted between Peru and Chile after a Peruvian court ordered the arrest of two Chilean military officers over alleged spying.
The court accused the officers of paying a Peruvian air force officer to reveal national secrets.
Chilean Foreign Minister Mariano Fernandez has denied his government has been involved in espionage.
But Peru's President Alan Garcia said he was leaving the Asia-Pacific summit in Singapore a day early over the row.
He also said he had cancelled planned talks with his Chilean counterpart, Michelle Bachelet, at the Apec summit.
"I am returning 24 hours earlier than scheduled so I can obtain complete and sufficient information (on the issue) and to be able to speak from Peru," Mr Garcia said, quoted by AFP new agency.
Reports in the Peruvian media said Lima had recalled its ambassador to Chile for talks.
Speaking in Singapore, Chile's foreign minister said: "Chile does not engage in espionage.
"We dismiss any charges [that] the Chilean government is involved in anything illegal in regards to relations between the two countries," Mr Fernandez added.
The Peruvian air force officer, Victor Ariza Mendoza, has been arrested and charged with spying.
Lima-based El Comercio reported that Mr Ariza had worked at the Peruvian embassy in Santiago in 2003.
Tensions are already strained between the two countries following a military exercise staged by Chile last month near its disputed border with Peru.
Peru and Chile have been embroiled in a bitter border dispute since the late 19th century, when Chile defeated Peru in the War of the Pacific.
The countries also disagree on their maritime border, and last year Peru took Chile to the international court in The Hague to seek a resolution.