The captain of the MV Lifeline, which was allowed to dock in Malta on Wednesday, has been interviewed again at the police headquarters in Floriana and is to be charged, probably on Monday.

Meanwhile, a Spanish migrant rescue NGO has said that Malta and Italy have refused entry to one of its ships. In a later statement, the Maltese government that it has effectively closed its ports to NGO rescue vessels until the Lifeline investigation is concluded.

In a statement the government said: "Following recent events that brought to the fore information that was previously unknown, Malta needs to ascertain that operations being conducted by entities using its port services and operating within the area of Maltese responsibility are in accordance with national and international rules. This includes, but is not solely limited to, the certification or registration of vessels involved. 

Given that there are investigations being carried out by independent authorities, and until these issues are clarified, Malta cannot allow entities, whose structure might be similar to that being subject to investigations, to make use of Malta as their port of operations, and to enter or leave the said port.  

This is also in view of judicial processes that might ensue, and in order for the Maltese authorities not to be considered to be approving of systems of operations that might eventually be found to be carried out in breach of their own and international rules."

The MV Lifeline was allowed to enter Malta on Wednesday after 8 EU member states, later joined by Norway, agreed to ‘share’ the 230 migrants on board. The vessel had been stranded off the coast of Malta for a number of days.

Both Italy and Malta have accused the captain, Claus-Peter Reisch, of failing to obey instructions to take the rescued migrants to Libya. The German NGO says it disobeyed that order because Libya is not a safe place.

The Maltese government has also said that there are irregularities with the vessel’s registration. While the NGO claimed that the vessel is registered under the Dutch flag, the authorities there said the vessel was registered as a pleasure yacht. Speaking at a press conference on Wednesday, Prime Minister Joseph Muscat said an investigation would be carried out and the vessel would be impounded in Malta.

A government spokesperson said the MV Lifeline is being detained "pending the necessary investigations according to national and international rules following the Captain’s decision to ignore directions given by Italian authorities coordinating the rescue and the vessel’s lack of registration according to the law."

"The process for the migrants to be shared by the 9 countries joining the ad hoc initiative led by the Prime Minister has already started and updates will be given in due course."

Asked about whether the government believes Libya to be a safe country, the OPM spokesperson said: "The safety of ports is dictated by international conventions which Malta fully complies to."

Replying to another questoin, the OPM said the government is "actively working to re-open its embassy in Tripoli."

In another development, the Spanish NGO Proactiva Open Arms has said that its ship Open Arms has been refused entry by both Malta and Italy. The NGO said it has saved more than 5,000 people in the space of a year, in operations coordinated by the Italian coast guard.

In March, Proactiva Open Arms had a boat impounded on the Italian island of Sicily after being accused of complicity in people-smuggling for refusing to hand over rescued migrants to the Libyan coast guard. But an Italian judge later backed the charity, saying that the fundamental rights of migrants could not be guaranteed in Libya.