The head of Tunisia's Red Crescent aid group has warned the condition of 40 migrants stranded on a boat stuck in the Mediterranean Sea has deteriorated as the vessel has been refused docking access for days.

Mongi Slim told The Associated Press Friday that the migrants have been stranded at sea for at least nine days and "the sanitary and psychological situation is very bad." The migrants include nationals from Bangladesh, Cameroon, Nigeria, Senegal and Egypt.

Tunisian authorities are still deciding whether to grant the boat entry after Italy, Malta and France refused. The migrants reportedly were at sea for five days before a Maltese ship picked them up and transferred them Monday to the Tunisian-flagged Sarost 5.

Malta had recently strongly refuted allegations in some reports quoting organisations saying that Malta broke international rules when directing rescued migrants to be disembarked in Tunisia.

A statement by the Maltese government had said the applicable conventions stipulate that disembarkation should take place at the nearest place of safety. In this case, Tunisia was the nearest place that satisfies the requirement as a safe place of disembarkation. The goverment said that it was reported to the Maltese authorities that the migrants initially refused to be rescued unless they would be taken to a European port, irrespective of international rules. Such a situation would not only have been illegal but would have created a precedent against the said rules.

It was only later that they accepted to board the ship that rescued them, and which complied with international rules, the government said.