Tripoli, Reuters—Turkey is introducing visa requirements for Libyans, Libyan officials said on Tuesday, pushing the North African country deeper into isolation.

Turkey had been one of the few countries which Libyans could visit without a visa and became a major holiday destination for Libyans seeking to escape the chaos and violence gripping the oil producer four years after the ousting of Muammar Gaddafi.

Libyans have struggled to get visas for European or Arab countries since most embassies left Tripoli a year ago when a rival faction to the recognized government seized the capital, Tripoli, expelling the official prime minister to eastern Libya.

Mohamed Tawil, a Foreign Ministry official from Libya’s Tripoli administration, said Turkey had notified the Libyan embassy in Ankara that Libyans needed a visa from September 25.

“We do not know the reason,” he told local Al-Nabaa TV, adding that Libya would now also require Turks to get a visa.

The Turkish Foreign Ministry told the embassy it was canceling an agreement from 2009 waiving visas for nationals of both countries, according to copy of the memorandum dated August 25 seen by Reuters.

There was no immediate comment from officials in Turkey.

Libya’s official government has accused Turkey of shipping weapons to the Tripoli government, charges denied by Ankara. Top army commander Khalifa Haftar said on Monday Qatar and Sudan were also supplying arms to the Tripoli side, charges previously denied by both countries.

It was not immediately clear whether those comments may have had an impact on the decision, or whether the move might be linked to Turkey’s growing crackdown on the Islamic State of Iraq and Syria (ISIS), which has gained a foothold in Libya by exploiting the security vacuum.

Turkey and Libya have strong trade ties. Thousands of Turks work in Libya, importing food and running supermarkets and restaurants. Many Libyan businessmen have bank accounts in Istanbul as local Libyan banks have few foreign ties.

Libya’s internationally recognized government said in February it would ban Turkish firms from doing business in territory under its control but the move was never enforced, residents say.