CAIRO (AP) — Rival Libyan politicians met on Wednesday for U.N.-sponsored political talks in Geneva aimed at ending the latest round of fighting over the country's capital, Tripoli.

Yet just hours later, the High Council of State, an advisory body to the western Tripoli-based government, sent a letter to the U.N. mission demanding that talks be suspended until “concrete progress is made" in ongoing military negotiations.

In the east of the country, the spokesperson for the rival Tobruk-based House of Representatives also requested a postponement and said it would pull its participants.

Power in Libya is divided between two rival governments, in the east and west of the country, and a patchwork of armed groups that support either administration.

In the wake of intensified international diplomatic efforts, the U.N. launched three parallel tracks of negotiations to push a cease-fire and resolve various crises in war-torn Libya. It's an uphill battle in a country with competing political structures.

Disagreements over the delegate list for Wednesday's talks swiftly surfaced, as rival officials objected to the last-minute inclusion of several independent politicians in the Tripoli delegation.

“We stress our agreement to choosing the group of additional representatives...to ensure it represents a cross section of Libyan society,” said the High Council of State letter.

Ghassan Salame, the U.N. envoy for Libya, briefed a closed meeting of the U.N. Security Council late Wednesday by video after the Geneva meeting which he organized.

Diplomats said after the U.N. briefing that Salame told members the eastern delegation from Tobruk didn't show up in Geneva, and he urged countries with influence to pressure the delegation to attend the talks.

Earlier this week, the U.N. said that military officials agreed on a draft cease-fire deal as they emerged from days of talks.

The declared cease-fire deal, now under review by Libya’s competing leaders, addresses the return of thousands of displaced civilians to Tripoli. But it makes no mention of key points of contention, such as the withdrawal of eastern-based forces or the demobilization of formidable militias loosely allied with the U.N.-supported Tripoli government.

Some cast doubt on whether the draft agreement was the breakthrough that the U.N. and U.S. embassy hailed it to be.

“This draft is nonsense,” said Abdul-Qader Hwaili, a member of the High Council. “In actuality, we have seen no progress in the military track. We cannot continue with the political meeting until we see it."

Peace negotiations have made halting progress over past weeks, as low-intensity clashes continue around Tripoli and weapons flow into the war-torn country despite world powers’ pledges to the contrary at a peace summit in Berlin last month.

The commander of the eastern forces, Khalifa Hifter, and his followers, who control the country’s east and south, launched an offensive to capture Tripoli last April. The fighting has displaced more than 150,000 people and killed hundreds of civilians.

Hifter receives extensive support from Egypt and the United Arab Emirates, as well as Russia and France. The embattled Tripoli government has increasingly relied on Turkey to supply military aid, including air defenses and fighters deployed from nearby Syria, to repel Hifter’s advances.