Saudi Arabia on Sunday condemned the Turkish parliament's approval of a military deployment to Libya, which is aimed at shoring up the UN recognised government in Tripoli.
Turkey's parliament approved the deployment on Thursday following a request for assistance by the beleaguered Government of National Accord.
"Saudi Arabia expresses its rejection and condemnation of Turkey's latest escalation in the Libyan issue," the official Saudi Press Agency said, citing the foreign ministry.
The GNA has been under sustained attack since April by eastern Libyan national army commander General Khalifa Haftar.
Haftar is backed by Turkey's regional rivals -- Saudi Arabia, Egypt and the United Arab Emirates.
"This Turkish escalation forms a threat to security and stability in Libya as well as to Arab security and regional security as it is interference in the internal affairs of an Arab country in flagrant violation of all relevant international covenants and principles," the SPA said.
Analysts warn that Turkey's deployment of troops risks plunging Libya deeper into a Syrian-style proxy war between regional powers
Libya has been mired in conflict since a NATO-backed uprising in 2011 toppled dictator Moamer Kadhafi, with rival administrations in the east and the west battling for supremacy.
Saudi Arabia's rivals, Turkey and Qatar, have taken the side of the GNA in the capital Tripoli.
No date was given for the potential Turkish troop deployment.