The special prosecutor for National Accountability Bureau in the Zulfi Bukhari case, Imran Shafique, tendered his resignation on Tuesday citing his wish to join the Islamabad Bar Association as an "independent professional lawyer".

In addition to representing the bureau which challenged the removal of Bukhari's name from the Exit Control List (ECL), Shafique was the NAB's special prosecutor in many high profile cases such as in the corruption reference against former finance minister Ishaq Dar, which subsequently led to Dar's assets being confiscated.

The interior ministry, responding to NAB's request, had placed Bukhari’s name on the ECL since he is facing an inquiry about “accumulating assets beyond known sources of income”.

However, Syed Zulfikar Ali Bukhari, aka Zulfi Bukhari, the special assistant to the prime minister on overseas Pakistanis and human resource development, has so far not submitted the documents related to his companies in the British Virgin Islands (BVI) which the investigators had sought from him.

In his resignation letter, a copy of which is available with Dawn.com, Shafique wrote: "I realise my national duty to combat corruption, and as a lead prosecutor in Ishaq Dar's case I would be available to offer my assistance, even after leaving NAB."

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He was inducted into the bureau as special prosecutor in May 2017 and has described his time serving NAB as a "great and profound learning experience".

NAB spokesperson Nawazish Ali, when asked to comment on the development, said that the anti-graft body had yet to receive the resignation letter.

Prior to joining the accountability bureau, Shafique was serving as an associate to former justice Shaukat Aziz Siddiqui — the Islamabad High Court (IHC) judge who was removed from his post by the president on the recommendation of the Supreme Judicial Council (SJC).