"All conspiracies of our political opponents will fail. No corruption allegations levelled against me," Sharif told media after questioning by the Joint Investigation Team or JIT.
"Our family was subjected to accountability during previous regimes," he added.
"The day that creates history & sets a much required & welcome precedent for others to emulate," Sharif's daughter Maryam Nawaz tweeted along with pictures of the PML-N leader and his top aides just before leaving for the Judicial Academy - the JIT's temporary secretariat - amid tight security.
The JIT chief Wajid Zia had summoned the Prime Minister to appear before the six-member probe team on June 15 with all documents relevant to the case.
The summons was issued to Sharif, 67, after he returned last Saturday from Kazakhstan where he had attended the Shanghai Cooperation Organisation (SCO) Summit.
In its judgement of April 20 in the Panama Papers case, the Supreme Court had constituted a JIT and empowered it to summon the Prime Minister, his sons and any other person necessary, to investigate allegations of money-laundering, through which the four apartments in London's posh Park Lane area were purchased.
Sharif has denied any wrongdoing.
The Joint Investigation Team had questioned Sharif's sons -- Hussain and Hasan -- last month over the family's alleged improper business dealings.
The court last year took up the case and issued a split decision over allegations of money laundering when Sharif was Prime Minister in 1990s.
On May 5, the Supreme Court set up a high-level six- member JIT to probe Sharif and his sons' alleged corruption in the Panama Papers case.
The JIT is bound to complete the probe in 60 days unless it is granted additional time.
It is for the first time that a sitting Prime Minister is appearing before a high-level probe team traditionally constituted to investigate high-profile criminal cases.
It is not yet clear that Sharif will be questioned for once or would be called again like his two sons.
The JIT probing the offshore holdings of Prime Minister Sharif and his children has also summoned his younger brother and Punjab Chief Minister Shahbaz Sharif, to appear before it on June 17.
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