Pakistan summoned US Ambassador Anne Patterson on Wednesday to lodge a protest over recent missile strikes by US drones in the country's tribal region along the border with Afghanistan.
"It was underscored to the ambassador that the government of Pakistan strongly condemns the missile attacks which resulted in the loss of precious lives and property," a statement from the country's foreign ministry said.
"It was emphasised that such attacks were a violation of Pakistan's sovereignty and should be stopped immediately," it added.
The statement came three days after a single missile fired from a pilotless US aircraft demolished the house of local Taliban commander Mohammad Omar in the tribal district of South Waziristan, killing him and 19 other people.
Pakistan's ungoverned tribal belt is believed to be a safe haven for Taliban and Al Qaeda militants launching cross-border attacks on US-led international forces in Afghanistan.
Islamabad has deployed more than 100,000 troops to contain movements of militants across the frontier and launched major offensives in two tribal districts.
The efforts have not ended the Islamic insurgency, prompting US forces to recently intensify air raids on Pakistani soil, but most of the strikes have caused civilian casualties, the Pakistani government said.
According to data compiled by the interior ministry, 301 of the 355 people killed in 32 US attacks this year were civilians, said a report published Tuesday in the English-language daily The News.
The civilian death toll has given rise to calls for ending cooperation in the international fight against terrorism.
"The attacks also undermine public support for the government's counterterrorism efforts," Pakistan's foreign ministry said in the statement.