The founder of Pakistan's Muttahida Qaumi Movement (MQM), Altaf Hussain has resigned as chief of the party.
Hussain said he was voluntarily handing over all authority and responsibilities as party leader to the MQM's Rabita (Coordination) Committee.
According to Dawn News, during a telephonic conversation with media from the UK, Hussain said he voluntarily decided to step down following a raid at his residence by Scotland Yard police some days ago.
He said he would not seek legal counsel or a solicitor but would plead his case himself if he were to be produced in court in the Imran Farooq murder case.
Dr Imran Farooq was one of the founding members of the MQM, then known as the Mohajir Qaumi Movement.
Farooq, who had also been living in exile in London since 1999, was stabbed to death on his way home from work in Green Lane on Sept 16, 2010 outside his residence, the report said.
The London Metropolitan police had stepped up investigation into the murder, and police searched two residential properties in London earlier this month as part of the ongoing probe, it added.