The development came shortly after the anti-graft watchdog re-submitted the reference regarding Flagship Investments, an offshore firm owned by Mr Sharif's children, Dawn reported.
The top accountability body had last week filed four references against the Sharifs as well as Finance Minister Ishaq Dar in light of the July 28 judgement of the Supreme Court in the Panama Papers case. However, the registrar of the accountability court returned two references and directed NAB to re-submit them by September 14.
The anti-graft body said the accused had been given ample time to explain and provide evidence regarding the accumulation of these assets but "they did not join the investigations before the NAB on the pretext of a review petition already filed before the Supreme Court of Pakistan against the July 28 verdict".
A five-judge larger bench of the apex court, headed by Justice Asif Saeed Khosa, is already hearing two separate review petitions moved by the ruling family, challenging decisions given by a five-member bench and a three-member bench of the apex court.