Malta, Italy, France and Germany are at loggerheads over who should be responsible for illegal immigrants saved in Libya's search and rescue area during the next EU anti-immigration patrol mission, Nautilus III.

Various attempts during the past days by Frontex and the European Commission to launch the mission have failed, The Times has learnt.

"We will be holding a technical meeting early next week to try to get everyone together and solve the outstanding problems.

"However, we can only try to facilitate things where it comes to technical matters. The dispute is also of a political nature and there, we can't intervene," a spokesman for Frontex said yesterday.

Nautilus III - a six-month long anti-immigration EU patrol mission covering the Sicily-Malta-Libya strait, was scheduled to start on April 22 but was postponed at the 11th hour because of a misunderstanding among the participating member states.

Although Frontex refused to specify which member state signalled the problem, it is understood Malta and Italy were behind this last-minute hitch. The mission will involve operations inside the zone designated by the International Maritime Organisation as Libya's SAR area and is likely to lead to the rescue of people who have tried to travel to Europe from Libya as a country of transit.

Because Libya has refused to take back people rescued during Frontex missions, Malta and Italy are arguing they shouldn't become the recipients of all illegal immigrants leaving Libya.

France and Germany, however, are refusing to share the burden. According to Frontex executive director Ilka Laitinen, the international rules on division of responsibility are clear.

"First and foremost it is the country in whose search and rescue area the incident takes place that is responsible," he said.

"In the case where it is not possible for that country to admit these people or it is not willing, the second rule is that it has to be the closest safe haven."

Mr Laitinen said, however, that there is also a political question of fairness, referring to Malta's proposal on burden sharing made last year.

Since June, when the proposal was made, the EU council has made no progress on the issue.

Mr Laitinen added that although it is not Frontex's responsibility to solve the burden sharing issue "we are very clearly dependent on what the policy is and how the different member states interpret their obligations".