Updated

The United Nations says Peru's coca eradication efforts cut the area under cultivation there by 17.5 percent last year, contributing to the Andean nation's highest cocaine prices in 15 years.

The U.N. said Wednesday that Peru's coca crop was down to 189 square miles (49,800 hectares) after dropping 3.4 percent from 2011 to 2012, the first decrease in seven years.

U.N. figures for 2013 for Colombia and Bolivia have not yet been released. They were the No. 2 and No. 3 cocaine-producing nations the previous year.

More than half Peru's coca crop is grown in the Apurimac, Ene and Mantaro river valley, where Shining Path rebels protect and profit from the illegal cocaine trade.

President Ollanta Humala announced this month that his government had delayed plans to forcibly eradicate there.