Akar was joined by other military officials as he met with the Chairman of the High Council of State to the Government of National Accord (GNA) of Libya, Khalid al-Mishri and the Minister of Interior of the Government for the GNA, Fathi Bashagha.
The unannounced visit came after the Turkish parliament on Tuesday extended for 18 months a law that allows the deployment of Turkish troops to Libya.
The decision was made despite the cease-fire deal that envisioned the departure of foreign forces and mercenaries within three months.
Libya was plunged into chaos after the 2011 NATO-backed uprising that toppled and killed longtime dictator Moammar Gadhafi.
The oil-rich country is split between the UN-supported government in the capital, Tripoli, and rival authorities based in country's east. The two sides are backed by an array of local militias as well as regional and foreign powers.
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In April 2019, east-based commander Khalifa Hifter and his forces launched an offensive to try and capture Tripoli, a campaign that collapsed after Turkey stepped up its military support of the UN-supported government.
Turkey deployed hundreds of troops and thousands of Syrian mercenaries to back up its Libyan allies.
The two sides signed a nationwide, UN-brokered cease-fire deal in October that included an exchange of all war prisoners.
Libya's rival leaders kicked off the exchange on Friday, according to the UN Support Mission in Libya, or UNSMIL.