Divers who inspected the hull of a tanker loaded with 750 tons of fuel that sank off southeast Tunisia detected no leaks on Sunday, officials said.
The Equatorial Guinea-flagged Xelo, which sank Saturday in the Gulf of Gabes, has settled on its side at a depth of almost 20 meters (65 feet), the environment ministry said.
"No leak has been detected," it said in a statement.
The inspection was carried out by divers accompanied by the ship's captain and engineer, said Mohamed Karray, spokesman for a court in Gabes city that is investigating the sinking.
The Xelo was traveling from Egypt to Malta when it went down.
With the scene sealed off by Tunisia's military, the defense ministry released pictures showing the vessel submerged on its side.
The crew of the Xelo had issued a distress call on Friday evening and sought shelter in Tunisian waters from bad weather before going down.
Tunisian authorities rescued the seven-member crew, who received first aid and were moved to a hotel.
Transport Minister Rabie Majidi said Sunday that rescue workers had checked during the operation that the valves were closed, and the team of divers ensured they were sealed and intact.
"The situation is not dangerous, the outlook is positive, the ship is stable because luckily it ran aground on sand," he told reporters.
The minister said the priority was to pump the diesel fuel and prevent any spillage or pollution.
As a precaution, protective booms have been placed around the wreck.
Environment Minister Leila Chikhaoui has also been at the scene in the port of Gabes to follow up on the incident.
Tunisian officials are investigating the itinerary of the tanker, which reportedly has Turkish and Libyan owners.
The Tunisia branch of the World Wildlife Fund has expressed concern about another "environmental catastrophe" in the region, an important fishing zone.
The tanker is 58 meters (63 yards) long and nine meters wide, according to ship monitoring website vesseltracker.com.
It began taking on water around seven kilometers (four miles) offshore in the Gulf of Gabes and the engine room was engulfed, according to the environment ministry.