A convoy of 96 trucks carrying sugar, oil, flour and rice from Tripoli passed the Ras Jedir crossing on Tuesday morning, said Naim Achibi, spokesman for the Libyan embassy in Tunis.
"These provisions are a donation from the government of national unity (in Tripoli) to help Tunisia tackle the acute shortages" of these products, he told AFP.
The operation is set to bring a total of 170 truckloads of supplies from Tripoli, he added.
Tunisia is in the grip of a downturn that has spiraled since its 2011 revolution, itself sparked by economic woes.
The country has seen repeated shortages of basic goods, from coffee to petrol in recent months, along with a political crisis following President Kais Saied's dramatic power grab in July 2021.
The border region between Tunisia and Libya is a hub for a thriving cross-border trade, both legal and illicit.
Libya tumbled into a morass of violence with the 2011 revolt that toppled dictator Moamer Kadhafi, and today two rival governments are vying for power.
But despite the conflict, revenues from Africa's biggest oil reserves make it relatively wealthy compared to its resource-poor neighbor.
Tunisia is also a major destination for Libyans seeking medical treatment.
The donation of food comes less than two months after Tripoli-based interim prime minister Abdelhamid Dbeibah visited Tunis in a move aimed at warming cool ties with Saied's government.