Libya’s parliament has ordered a special force to be sent within one week to “liberate” all rebel-held ports in the volatile east, officials said on Monday, raising the stakes over a blockage that has cut off vital oil revenue.

The conflict over oil wealth is increasing fears that Libya may slide deeper into chaos or even splinter as the fragile government fails to rein in dozens of militias that helped oust Muammar Gaddafi in 2011 but now defy state authority.

The rebels, who have seized three ports and partly control a fourth in the OPEC member country, said they had dispatched forces to central Libya to deal with any government attack.