U.S. President Barack Obama has defended the use of drone strikes in Pakistan, which U.S. officials have never before publicly acknowledged.

Speaking during an online town hall discussion Monday, Mr. Obama said the drone attacks have been used to target al-Qaida and its affiliates, and that many of the strikes have been in Pakistan's Federally Administered Tribal areas.

The president said the operations are used for “very precise, precision strikes,” and he said the U.S. does not authorize the attacks “willy-nilly.” He said it is a targeted, focused effort against “active terrorists” in difficult-to-reach locations.

Prior to Monday's remarks, U.S. officials had never confirmed the missile strikes against militants in Pakistan's tribal areas, but they have anonymously confirmed such attacks to various news outlets.

Pakistan has publicly condemned the drone strikes as a violation of the country's sovereignty, but they are believed to be carried out with the help of Pakistani intelligence.