Nigeria's Dangote oil refinery is expected to carry out a 40-day planned maintenance at its petrol-making unit in December, instead of in October as previously planned, industry monitor IIR said.

The Dangote refinery did not immediately respond to a request for comment.

The 650,000 barrel-per-day refinery will carry out catalyst replacement and reactor repairs in December's maintenance round, expected to start on December 4, IIR said.

Dangote restarted its petrol-making residue fluidised catalytic cracking unit on July 12, IIR added.