Sharif, 68, and his daughter left for London via Qatar from the Lahore airport this morning.
"Leaving for London. We will be back next week. Can't wait to meet and hug Ami (mother)," Maryam tweeted.
Kulsoom is in an advanced stage of throat cancer and is undergoing treatment in London.
On the other hand, the caretaker government has neither rejected nor accepted the National Accountability Bureau's to place the Sharif family members on the ECL. The caretaker government could not decide whether to entertain NAB's request or not in this regard, an official of interior ministry said.
Former PML-N chief Sharif, his children and son-in-law are facing three corruption charges in the accountability court for money laundering and illegal offshore holdings.
The trial is in the final stage as the Supreme Court has directed the trial court to conclude the case by July 10. The corruption references against Sharif and his family were filed after his ouster as prime minister in July last year in the Panama Papers case.
Sharif had complained of not getting a "fair trial". He alleged the court had already decided to pass a verdict against him before the July 25 general election.
In a letter to the interior ministry, NAB said, "This matter is agitated again in view of the fact that references against the accused persons Nawaz Sharif, Maryam Nawaz, Hasan Nawaz, Hussain Nawaz, Capt (R) Mohammad Safdar, are in the final stages of trial. There is apprehension that they may leave the country to avoid legal outcome of the judgment which is expected to be announced shortly".
It also asked the ministry to put former finance minister Ishaq Dar on the ECL and initiate the process to bring him back to the country as well as the two sons of Sharif - Hassan and Hussain - through Interpol.
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On February 14, NAB had sent a similar letter to the ministry, but the then PML-N government did not place the Sharifs' names on the ECL. It reportedly declined the request on the grounds that names could only be included in the no-fly list by a court order.
The political future of Sharif, who heads the country's most powerful political family and is the de-facto leader of the ruling PML-N, is uncertain and he could be jailed if convicted.
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