A top American military officer says Pakistan has taken steps to prevent fertilizers made in Pakistan from being used for roadside bombs targeting American troops in Afghanistan.

Brig. Gen. Robert P. Walters Jr. spoke Monday in Islamabad on ways to counter the bombs often referred to as improvised explosive devices. He's deputy director of the U.S. military's Joint IED Defeat Organization.

Many of the homemade bombs used in Afghanistan use chemicals from fertilizer produced in Pakistan.

The U.S. has pushed Pakistan for greater regulation of the fertilizer. Pakistan says the fertilizer is necessary for its vital agriculture sector.

Walters praised Pakistani efforts to reinforce its border to curb fertilizer smuggling into Afghanistan. He also said the Pakistani company that makes the fertilizer was moving to restrict its use in IEDs.