The aircraft was on a “reconnaissance and patrol mission and suffered a technical problem resulting in an emergency landing” in southern Tunisia, said a statement from an administration based in eastern Libya.
Haftar’s self-styled Libyan National Army, which backs the eastern administration, launched an offensive in April to try to seize Tripoli from the UN-recognised Government of National Accord (GNA).
Tunisia’s defence ministry said the jet landed early Monday on a road near Medenine city, which lies some 100 kilometres (60 miles) from the Libyan border.
The ministry mobilised a fighter jet “to intercept and identify the aircraft, but it had to make an emergency landing”, said the ministry, adding that one colonel was on board.
Onlookers including children gathered near the jet, while the pilot spoke to Tunisian authorities.
“We saw two planes flying around 7:15 am this morning,” a local resident told AFP.
“And then one of them landed here,” he added.
The jet was transporting two bombs, said an AFP photographer at the scene where the warplane had been cordoned off at the roadside.
Libya’s internationally-recognised GNA in Tripoli also said the jet belonged to pro-Haftar forces.
More than 1,000 people have been killed in the battle for Tripoli, according to the World Health Organization, while more than 100,000 people have been displaced by the violence.