Stephanus Block, the Dutch security minister, said: “Just opening more ports will not solve the problem”.

Theo Francken, a Belgian state secretary, joked: “I don’t think we’re going to open Belgian ports. No”.

The EU talks took place amid a surge in people coming via Libya to Italy and amid near-record migrant fatality rates in the central Mediterranean.

Italy had called for solidarity, but its interior minister, Marco Minniti, said on Thursday that the ports proposal had met with “difficult opposition”.

Estonia, which holds the EU presidency, did not mention ports in its communique on the meeting.

It said the EU and Libya should do more to stop people from coming. It also said there should be “rapid returns” of economic migrants from Italy and that the EU should be “using all possible levers and incentives” to clinch readmission deals in Africa.

It said NGO rescues should take place “within a set of clear rules” amid warnings on “pull factors” for migrants.

The European Commission on Wednesday proposed to resettle 37,000 refugees from Africa to ease the burden on Italy, but the Estonian statement made little mention of that.

It also made little mention of Commission quotas for relocating 160,000 asylum seekers from Italy and Greece.

“Returns policy is … the key word in the migration crisis. If we can send people back this will be the first and most important preventative measure, so that they understand there is no reason to come here,” Estonian interior minister, Anders Anvelt, said.

“Illegal migration and also economic migration must be stopped,” he said in Tallinn.

The EU migration commissioner, Dimitris Avramopoulos, said Thursday’s conclusion was that “we have to do more to improve implementation of what has already been agreed”.

He was among the few who praised the work of NGO rescue boats.

Morgan Johanson, Sweden’s migration minister, said: “There may be a limit where cooperation between these voluntary organisations and human traffickers has gone as far as human trafficking is helped”.

"It is necessary to raise the awareness of NGOs that they … do not promote illegal immigration,” Spanish interior minister Juan Ignacio Zoido said.

Italy is currently drafting the NGO rules, which will be examined by the EU before it gives its nod.

Germany’s De Maiziere also spoke critically of NGO activity.

“If transponders [boat sensors] are deliberately turned off [by NGOs] in order to obscure the location, then that does not arouse confidence,” he said.