Colombia's president said Saturday that U.S.-backed drug sprayings will resume in the world's largest cocaine-producing region after being suspended earlier this year, according to the state news agency.

The decision could spark strong reaction from thousands of farmers in southern Putumayo state who earn a meager living growing coca — the raw ingredient of cocaine.

Speaking from Puerto Asis, the provincial capital, President Andres Pastrana said the brief spraying campaign would target large coca plantations. He didn't indicate when it would begin, the news agency, known as ANCOL, said.

Fumigations in Putumayo and other drug growing regions have been suspended and restarted frequently in the past two years because of opposition from farmers and pickers who say they have no other way to live.

The campaign is being funded by U.S. aid. President-elect Alvaro Uribe, whose term begins Aug. 7, is seeking more drug-fighting aid from Washington to expand fumigations. Colombia is the world's largest coca producer, and this production centers in Putumayo.