The populist Italian interior minister Matteo Salvini has called for migrant reception centres to be set up on the external borders of southern Libya after a meeting with the African nation’s leaders in Tripoli.

He said the proposal, one of many in a Italian package designed to crack down on migration, will be put to EU heads of governments at a meeting on Thursday.

It was the first visit to Libya by a member of the new Italian government, which was elected on a wave of public unrest about the arrival of more than 500,000 mainly African migrants trafficked across the Mediterranean by Libyan smuggling gangs over the past four years.

Italy’s rightwing coalition, led by Salvini’s anti-immigration League, surged to several victories in local elections at the weekend, wresting control of three large cities traditionally held by the left.

It was also Salvini’s first official overseas visit since he was appointed to the interior ministry, and underlines how much the fate of the populist government is dependent on what happens to migration within Africa.

Salvini has already caused fury among European politicians by unilaterally closing Italian ports to NGO ships that have picked up migrants in distress in international waters.

His visit came as the Associated Press reported that Algeria has abandoned more than 13,000 migrants in the desert in the past 14 months, including pregnant women and children, stranding them without food or water and forcing them to walk, sometimes at gunpoint, under temperatures of up to 48C (118.4F).

The news agency said that while some made it to Niger countless others had died in the desert.

According to the AP, Algeria’s mass expulsions have picked up since October 2017 as the EU renewed pressure on north African countries to head off migrants going to Europe.

Speaking at a press conference in Tripoli, Salvini said: “On Thursday in Brussels, we will jointly support with Libyan authorities the setting up of reception and identification centres south of Libya, on the external border of Libya, to help Libya as well as Italy, block migration”.

“Neither Italy or Libya can be alone in protecting their borders,” he added.

The UN-backed Libyan government based in Tripoli said it will not allow migrant camps in Libya if they are run by foreign personnel, a condition that suggests that Salvini’s proposed camps would have to be placed on the borders of Libya with neighbouring countries such as Chad and Niger. Still, it is not clear whether governments there would be willing to host the migrant centres.

Ahmed Maiteeq, the deputy premier of Libya’s government of national accord, explained his country “categorically refuses” to set up foreign-run camps on its own territory, saying this would break Libyan law.

He said Libya would invite European countries bordering the Mediterranean to a summit on migration in Tripoli at the beginning of September.

At present, UN staff from the International Organisation for Migration and the UN High Commission for Refugees are allowed to visit Libyan reception centres, but the visits are sporadic, and the UN agencies have little formal power to demand changes to the often brutal regime. The European parliament has called for the EU to withdraw cooperation from the camps.

Salvini said he wanted to do more to help train the Libyan coastguard, but he did not call for European border guards to be placed on the shores of Libya, an idea proposed by the Austrian chancellor Sebastian Kurz. Italian navy personnel are on shore in Libya but do not directly participate in patrols.

Figures show since last summer the coastguard has been responsible for more than 40% of the migrants that are now rescued or intercepted.

But the Libyan navy are seeking extra boats and equipment to beat back both the traffickers and the NGOs waiting to pick up boats in distress outside Libyan sovereign waters. Libya would also like the UN arms embargo lifted.

There have been growing complaints that the Libyan coastguard has been using increasingly aggressive methods to push rafts packed with migrants back to the coast land. It has also been alleged some of its members are in league with the traffickers.

Irregular sea arrivals to Italy are down by 78% year on year, with NGOs carrying out over 40% of search and rescue operations in 2017 and 2018. Yet more than 51% of Italians believe flows are as high or higher than last year’s.

In other trends, the numbers of dead or missing trying to cross the Mediterranean has started to rise with more than 1,000 estimated deaths this year.