The U.N. envoy for Libya is urging the Islamist-led government that seized the country's capital to sign a peace deal that would establish a unity government in the North African nation where fighting and chaos is worsening.

Bernardino Leon emphasized to the U.N. Security Council on Wednesday that "the door remains open for them to join." He stressed that the U.N.-brokered agreement "is also the fruit of their hard work, and they should not be on the sidelines."

The government in Tripoli, which is backed by militias, took part in early stages of talks but refused to participate in later discussions.

Members of Libya's internationally recognized parliament, now based in the eastern city of Tobruk, and local and regional leaders initialed the agreement in Morocco on July 11.