Guinea's CBG halted bauxite exports on Sunday afternoon after repairs to a conveyor belt used to load ships failed, a company source told Reuters.

The company's exports had restarted from a week-long shutdown earlier in the day after repairs to the conveyor were completed, but the staples the company had used to stitch the conveyor together broke by afternoon, the source said.

The source did not say how long the exports would be halted.

CBG, a joint venture between the Guinean government, Rio Tinto and Alcoa , is the world's largest single bauxite exporter company with around 13 million tonnes of exports per year.