Pakistan's ambassador to the United States Sherry Rehman has resigned following the country's landmark election held over the weekend which was won by former prime minister Nawaz Sharif.
Rehman, 52, was appointed to the post in 2011 following a scandal which saw her predecessor Hussain Haqqani resign over an alleged memo seeking US help in preventing a coup following the killing of terror chief Osama Bin Laden.
She is a prominent figure in the Pakistan People's Party, which led the outgoing government but saw its support collapse at the polls on Saturday.
"Congratulating the new parliament on its election ambassador Sherry Rehman has sent in her resignation to the PM," the Pakistan Embassy in Washington DC said on its official Twitter account early Tuesday Pakistan time.
"It is time a new envoy came in as quickly as possible so that there is no gap in the relationship," it said in another tweet.
An aide of Rehman, who did not wish to be named, confirmed the move. She is expected to resume her role as president of the progressive Jinnah Institute think-tank she founded in Islamabad.
An official at the ministry of foreign affairs could not confirm if the resignation had been received but said: "Rehman was appointed by the outgoing government. It is normal for diplomats to resign when new governments come to power."
Rehman, who previously served as information minister and was a member of parliament from 2002 to 2011, authored several pro-women bills in parliament and was a close aide to slain former premier Benazir Bhutto.
In late 2010 she sparked fury among religious groups by lodging a private member's bill seeking to abolish capital punishment for blasphemy after a Christian mother of five was sentenced to death.
In February police announced they would open an investigation into blasphemy charges over comments made in a television show in 2010.