Islamabad, June 4 : Pakistan's National Accountability Bureau (NAB) has summoned Pakistan Tehreek-e-Insaf (PTI) Chairman Imran Khan and his wife, Bushra Bibi, on June 7 for the investigations of the 190 million pounds settlement case related to the transfer of funds from Britain's National Crime Agency (NCA) account, the media reported on Sunday. As per details, NAB Rawalpindi has summoned the former first lady to record her statement as a witness for being the trustee of the Al-Qadir University Trust, while the former Pak Prime Minister has been called by the combined investigation team (CIT) of the anti-graft watchdog, The News reported. The sources said that the CIT was not satisfied with the PTI chief's reply which he submitted during his last appearance before NAB, Rawalpindi, on May 23. They said that the former premier had been directed to answer the questionnaire on June 7, given to him on May 23, the media reported on Sunday. The law binds NAB, which is an autonomous anti-corruption body, to inform -- whoever it is summoning -- whether they are being summoned as an accused or a witness to record the statement, The News reported. Following the procedure, the NAB's CIT has already recorded the statements of ministers of the previous government. The body has also asked for the records of all the donations received from Al-Qadir University Trust and those who donated. It may be noted that an accountability court had granted bail to the PTI chief in the corruption case till June 19 last week after the Islamabad High Court (IHC) directed him to approach the relevant forum for bail. Meanwhile, the NAB officials had informed the court that Bushra Bibi's arrest was not required in the case but she should cooperate with the anti-graft body whenever summoned for investigations. /IANS