Kamilaroi former Aussie Test quick Jason Gillespie has resigned as Pakistan red ball coach with the bulk of his two-year contract still remaining, and two weeks out from the start of their two Test series with South Africa.

Former Pakistan international Aqib Javed has been appointed into the role as an interim replacement, the Pakistan Cricket Board confirmed on Friday, Australian time.

Aaqib was appointed white-ball coach last month, filling the role briefly taken on by Gillespie for a bilateral limited overs series in Australia, after former South African international Gary Kirsten exited the post.

Both Gillespie and Kirsten had both signed on to their respective positions in April.

Gillespie's decision comes after his former South Australia teammate Tim Nielsen's departure as a high performance coach in the Test setup with his contract not renewed.

According to reports, Gillespie was not impressed that he wasn't consulted by the PCB about Neilsen's future.

He had previously spoken candidly about both frustrations and a "pretty turbulent" period by both player and coach.

"What I've learned is you've really got to - in Pakistan cricket, just go with the flow because things change very, very quickly," Gillespie told ABC in November.

"You know, I'm the sort of person who likes to swing for a goal, but, but I'm learning that I need to float with the tide, so to speak."

Before replacing Gillespie's interim role as white-ball coach, Aaqib was already serving as a selector for the Test side - a responsibility Gillespie was recently stripped of.

Pakistan have five white-ball games remaining before their first Test in South Africa, starting December 26.

Gillespie coached Pakistan to a 2-1 home series win over England in October.