The comments from Italian Foreign Minister Angelino Alfano came as a second non-governmental organisation announced it was suspending operations in the area in response to the Libyan move.
The Libyan government "is ready to put in place a search and rescue zone in its waters, work with Europe and invest in its coastguards," Alfano told La Stampa daily on Sunday.
"This sends a signal that the balance is being restored in the Mediterranean."
Libya's navy last week ordered foreign vessels to stay out of a coastal "search and rescue zone" for migrants headed for Europe, saying the measure was aimed at non-governmental organisations it accuses of facilitating illegal migration.
Six years since a revolution that toppled longtime dictator Moamer Kadhafi, Libya has become a key departure point for migrants risking their lives to cross the Mediterranean to Europe.
Tens of thousands of migrants have resorted to paying people traffickers for the journey, often on overcrowded and unseaworthy boats, and charities have dispatched ships to rescue them from drowning.
Meanwhile, Libya and Italy -- where the vast majority of migrants land -- have worked together to stem the flow, with Italy also moving to rein in NGOs helping the multinational rescue operations by making them sign up to a new code of conduct.
"We need a significant, I repeat a significant European economic investment in Libya and in Africa," Alfano said.
"Europe has to decide if the theme of migration flows is an absolute priority on the same scale as the economy. For us, it is".
The Libyan measure prompted the German aid group Sea Eye to announce on Sunday it is suspending its migrant rescue operations in the Mediterranean, citing security concerns.
Sea Eye said in a statement that it was with "a heavy heart" that it made its decision, after the Libyan government's "explicit threat against the private NGOs".
"Under these circumstances, a continuation of our rescue work is not currently possible. It would be irresponsible towards our crews," Sea Eye founder Michael Buschheuer said.
The move came one day after Doctors Without Borders (MSF) had said it was also halting the use of its largest boat in the area because of an "increasingly hostile environment for lifesaving rescue operations".
Migrant aid ships have played a key role in assisting rescue operations.
Sea Eye said it has helped save some 12,000 lives since April 2016, and cautioned on Sunday that the retreat of aid groups from Libya's coast was putting lives at risk.
"We leave behind a deadly gap in the Mediterranean," Buschheuer warned.
But Alfano said MSF's decision "is also within the framework of a balance readjustment".
The number of migrant arrivals in Italy in July was down dramatically on the same month last year, suggesting efforts to train up and better equip the North African country's coastguard could already be having an impact.
The interior ministry said 11,193 new arrivals had been registered in July, compared with 23,552 in July 2016.
Arrivals for the first seven months of this year were 95,214, up 0.78 percent on the same period last year.
Some 600,000 mostly African migrants have arrived in Italy from Libya since the start of 2014.