Islamabad:
Pakistan on Thursday summoned a senior US diplomat in Islamabad to protest against a string of drone strikes since last week, saying the attacks by the spy planes were unlawful and a violation of the country's sovereignty.
"The US Embassy was today demarched on recent drone strikes in North Waziristan. A senior US diplomat was called to the Ministry of Foreign Affairs and informed that the drone strikes were unlawful, against international law and a violation of Pakistan's sovereignty," said a brief statement issued by the Foreign Office spokesman.
"It was emphatically stated that such attacks were unacceptable," the statement said.
Over 20 suspected militants, a majority of them members of a Taliban faction led by Hafiz Gul Bahadur, were killed in the four drone strikes in North Waziristan since August 18.
Ten militants were killed in two drone strikes in North Waziristan on August 19.
Most of the attacks were carried out in Shawal area. The region is dominated by Bahadur's fighters, who often target US and other foreign troops in Afghanistan.
The US has been pushing Pakistan to act against Taliban and Al Qaeda elements in North Waziristan.
Defence Secretary Leon Panetta recently claimed Pakistan was preparing an operation against the Taliban in North Waziristan.
However, Pakistan Army chief Gen Ashfaq Parvez Kayani has said his forces will undertake an operation in North Waziristan "at a timeframe of our choosing and determined only by our political and military requirements".
No operation will be launched due to "outside pressure", he said.