The man poised to become Pakistan's next prime minister says he has "good relations" with the United States, but called the CIA's drone campaign in the country's tribal region a challenge to national sovereignty.
Nawaz Sharif spoke to reporters from his family's estate outside the eastern city of Lahore two days after his Pakistan Muslim League-N party won a resounding victory in national elections.
His comments were the first indication since the vote about how he would approach relations with the US, a strategic ally with whom Pakistan has often been at odds.
Some of his rhetoric on the campaign trail suggested he could have a more adversarial relationship with Washington than the outgoing government. Mr Sharif also was outspoken in his opposition to drone strikes, which are unpopular in Pakistan.
However, analysts caution that while such rhetoric sells on the campaign trail where anti-American sentiment is high, he would likely take a more nuanced approach to US relations once in office.
"I think we have good relations with the United States of America. We certainly have to listen to each other," he said. "If there are any concerns on any side, I think we should address those concerns."
The CIA's drone campaign targeting al Qaida and other militants in the tribal regions has been extremely controversial in Pakistan where people say it frequently kills innocent civilians - something Washington denies - and that it violates Pakistan's sovereignty.
"Drones indeed are challenging our sovereignty. Of course we have taken this matter up very seriously. I think this is a very serious issue, and our concern must be understood properly," said Mr Sharif.
Pakistan occupies a strategic location next to Afghanistan and will likely play a strong role in any reconciliation deal with Taliban militants there. Also, much of the American military equipment that must be shipped out of Afghanistan when the international coalition there ends its combat mission in 2014 will go through the port city of Karachi in southern Pakistan.
Mr Sharif said that he would facilitate the U.S. withdrawal from Afghanistan. "American troops are being withdrawn in 2014. We will extend full support to them. We will see that everything goes well and smoothly," he said.