Colombia's Environment Minister Sandra Suárez will have to explain to her country's Congress the U.S. financing received for spraying glyphosate herbicide on illegal coca plantations in nature reserves. Lawmaker Jorge Robledo, of the leftist Independent Workers' Movement, called for Suárez to testify before Congress about the U.S. measure — part of its foreign operations program — to finance fumigation efforts to eradicate illicit drug crops in Colombia's nature parks.

Robledo says it is an attack on the environment and collective heritage of the Colombian people.

The Colombian government says there are 15,000 hectares planted with coca, the raw material for cocaine, in the country's nature parks.

Colombia, the second in biodiversity worldwide, after Brazil, has set aside some 10 million hectares as natural preserves, which are also home to several indigenous communities.