BENGHAZI, Libya (Reuters) - A high-level delegation from Libya’s parallel government in the east visited the main southern city of Sabha on Monday after its forces this month seized control of the city, an official said.

The eastern government is allied to Khalifa Haftar, whose Libyan National Army (LNA) launched a campaign this month in southwestern Libya.

Sabha had been nominally under the control of the internationally recognised government in Tripoli but in reality was run by local groups including tribes.

Control of Sabha is seen as vital for securing southern Libya’s oilfields, one of the stated goals of the LNA campaign.

The interior, health and junior justice ministers of the eastern government, which is based in Benghazi, were seen meeting local officials in the municipality of Sabha in pictures sent to Reuters by members of the visiting delegation.

The officials later visited the main hospital and a court, journalists said.

Tripoli officials could not be reached for comment on the visit, which further highlighted the internationally recognised government’s continued lack of authority in most of Libya.

Tripoli-based Prime Minister Fayez al-Serraj said during a visit to Vienna on Monday that “many things” were not going well in the south, but he did not allude to the visit by the eastern delegation or to the LNA advance.

“Regarding the south we need better support for our security forces. We need more cooperation between all security forces,” he said.

The LNA has secured Sabha airport and other strategic sites in the area in recent days, after local groups handed them over without a fight.

The LNA says its campaign is aimed at combating militant groups and securing oil facilities in the south, which include El Sharara oilfield, Libya’s biggest.

On Monday LNA forces killed a suspected al Qaeda fighter called Adel Ahmed al-Abdaly when they stormed his house in Sabha, LNA spokesman Ahmed Mismari said. Otherwise the city has been largely quiet since the arrival of the LNA.

Al Qaeda and Islamic State have been using southern Libya as a base for attacks in Libya and neighbouring countries, exploiting a security vacuum created by the fall of dictator Muammar Gaddafi in a 2011 rebellion backed by NATO air strikes.