Turkey and Russia agreed on Wednesday to press for a ceasefire in war-ravaged Libya, but Ankara said the leader of the eastern forces was illegitimate and must withdraw from key positions for a credible truce to take hold.
Moscow and Ankara are among the main power brokers in Libya's conflict while supporting opposing sides. Russia backs the eastern-based forces of renegade military commander Khalifa Haftar, while Turkey has helped the Tripoli-based Government of National Accord (GNA) repel Haftar's attempt to storm the capital.
"We've just reached an agreement with Russia to work on a credible and sustainable ceasefire in Libya," President Recep Tayyip Erdogan's top security adviser, Ibrahim Kalin, told Reuters news agency.
Kalin said any deal must be based on a return to what he said were the Libyan front lines in 2015, requiring Haftar's forces to pull back from the strategic city of Sirte - gateway to Libya's eastern oilfields - and al-Jufra, an airbase near the centre of the country.
"For the ceasefire to be sustainable, Jufra and Sirte should be evacuated by Haftar's forces," Kalin said.
Battle for Sirte
Turkish-backed forces allied with the UN-recognised government in the capital are mobilising on the edges of Sirte and have vowed to retake the Mediterranean city along with the inland al-Jufra airbase.
The United States has said Moscow sent warplanes to al-Jufra via Syria to support Russian mercenaries fighting alongside Haftar's self-styled Libyan National Army (LNA). Russia and the LNA both deny this.
Egypt, which also backs the LNA, has threatened to send troops into neighbouring Libya if the GNA and Turkish forces try to seize Sirte. The Egyptian parliament on Sunday gave a green light for possible military intervention.
Kalin said any Egyptian deployment in Libya would hamper efforts to end the fighting and would be risky for Cairo. "I believe it will be a dangerous military adventure for Egypt."
Egypt's Foreign Minister Sameh Shukry said on Wednesday achieving a political solution in Libya requires a "firm" response to "extremists" and foreign interference, which "not only threaten Egypt's interests but also the security of Mediterranean countries".
He noted a peace proposal announced in Cairo last month aimed at stabilising Libya and eliminating armed fighters and militias in the oil-rich country.
The proposal announced by President Abdel Fattah el-Sisi included a ceasefire and a new elected presidential body representing the three Libyan regions. The east Libya camp accepted the proposal, dubbed the Cairo Declaration, while the Tripoli-based administration rejected it.
Libyans fear the unknown as Egypt, Turkey ramp up war in Sirte.
Wednesday's joint agreement by Turkey and Russia on their ceasefire efforts included a call for measures to allow humanitarian access to those in need and efforts to promote political dialogue between the rival Libya sides.
But Kalin said Haftar had violated previous truce deals and was not a reliable partner, suggesting other figures in the east should play a role.
"We don't take [Haftar] as a legitimate actor anyway," he said. "But there is another parliament in Tobruk. There are other players in Benghazi. The negotiations will have to take place between them."
The LNA has itself sent fighters and weapons to bolster its defence of Sirte, already badly battered from earlier phases of warfare and chaos since the 2011 revolution against longtime autocrat Muammar Gaddafi.
Russia's foreign ministry said it backs a ceasefire and political talks that would culminate in united governing authorities. Russia has received senior delegations from both sides of the Libyan conflict in Moscow and tried and failed to get Haftar to sign up to a ceasefire agreement.
'All kinds of bullying'
Shukry's comments came in separate phone calls with France's Foreign Minister Jean-Yves Le Drian and German Foreign Minister Heiko Maas, according to a statement from Egypt's foreign ministry.
United Nations orders probe into human rights abuses in Libya
Erdogan, meanwhile, chaired a high-level security meeting that focused on Libya on Wednesday.
A statement released at the end of the National Security Council meeting said Turkey would not hesitate to take all steps necessary against "all kinds of bullying" taking place in Libya.
The council promised to "stand by the people of Libya against any tyranny".
Egypt, the United Arab Emirates and other foreign powers have provided Haftar's forces with critical military assistance.
Russia also sent hundreds of mercenaries through the Wagner Group, a private military company.
Libya was plunged into chaos when a NATO-backed uprising in 2011 toppled Gaddafi who was later killed.