More than half of Libya's oil export potential may be back online after rebel forces handed over control of two key ports, the Libyan National Oil Co. said.

Ras Lanuf and Es Sider, two oil ports that account for as much as half of Libya's full export potential of 1.3 million barrels per day, were handed over to government control last week. Mohammad el-Harari, a spokesman for the state-owned National Oil Co., said a legal clause over the terminals, force majeure, was lifted Sunday.

Force majuere frees a company from its contractual obligations because of circumstances beyond its control.

Combined, the two ports can ship as much as 560,000 barrels of oil per day. The spokesman said it was unclear when new Libyan oil would find its way to the international market.

The Libyan government brokered a deal April 6 with eastern rebel leaders to re-open two other export terminals. An eight-month blockade from rebels seeking more autonomy for the region known as Cyrenaica had cut Libya's oil export potential dramatically.

Libya since the end of civil war in 2011 has struggled to maintain a stable level of oil production. Early 2014 output has been limited to around 250,000 bpd, though it had peaked after the end of the conflict at more than 1 million bpd.