Italy is seeking to have seven boats carrying roughly 1,000 migrants needing rescue off Libya taken back to North Africa, according to a Spanish aid group.

Proactiva Open Arms, which has rescued thousands of migrants in the Mediterranean, said the Italians want the Libyan coast guard to conduct the rescues and return the migrants.

Proactiva said in a tweet that Italian coast guard authorities who coordinate rescues sent out advisories to all ships in the area but told the aid group: 'We don't need your help.'

In a tweet on Sunday, hard-line interior minister Matteo Salvini said: 'It's right that the Libyan authorities intervene, as they've been doing for days, without having the NGOs interrupt them and disturb them.'

The Mission Lifeline said the vessel was stranded in international waters of Malta. The island nation's military provided humanitarian assistance but the ship was not allowed to land there

It comes days after Salvini refused to let a rescue boat with 224 migrants on board dock in Italy, saying those on board 'will only see Italy on a postcard'.

Salvini said the ship, operated by German aid group Mission Lifeline, had loaded the migrants in Libyan waters against the instructions of Italy's coast guard.

Mission Lifeline denied Salvini's claims, saying it conducted the rescue in international waters and asked for a safe port, which had not been assigned.

Barcelona Mayor Ada Colao, who has previously offered her city as a port when Italy refused entry a rescue ship, repeated her willingness to take in the migrants.

She urged her country's Prime Minister Pedro Sanchez to intervene to allow Proactiva's ship to 'save lives.'

Colao said: 'Italy wants to leave the migrants in the hands of Libya, where they torture, rape and enslave' migrants.

Malta's home affairs minister, Michael Farrugia, and Italy's transport minister, Danilo Toninelli, also engaged in a Twitter war of words Sunday over which country was being more 'inhuman' about the fate of the Lifeline and its passengers.

Italy has demanded Malta let the Lifeline dock since it's currently in Maltese waters. Farrugia tweeted Sunday 'Why weren't they allowed to dock immediately in Italy, like Italy is now asking Malta? That's the true inhumanity.'

Migrants on an inflatable boat beeing rescued before boarding the Lifeline sea rescue boat

The new anti-migrant government in Rome has refused to let aid groups dock in Italian ports, arguing they are encouraging smugglers.

Salvini has threatened that Italy will withhold its payments to the EU if it does not get more help on the migrant issue.

But Italy's rescue coordination centre had still engaged with the groups at sea during actual rescues up until Sunday.

Italy's populist 5-Star Movement demands that European countries act to deal with hundreds of thousands of migrants on the continent, warning that the future of Europe is at stake.

The 5-Stars, who are in a ruling coalition with the anti-migrant League party, penned a blog entitled The Migrant Hypocrisy Sinks Europe as EU leaders met in Brussels on migration.

The post complained that few countries came close to accepting the redistributed migrants they pledged to under a failed 2015 EU plan to ease the burden on Italy and Greece.

The post said: 'It's time for Europe to find itself again in the principles that everyone preaches, but few sincerely practice,' saying what is at stake is 'the future of Europe as a political community and its values.'