A judge in Sicily has dropped an investigation into two members of the Spanish aid group Proactiva Open Arms that stemmed from a standoff last year when the crew refused to hand over 218 migrants rescued at sea to the Libyan coast guard.

Proactiva welcomed Wednesday's decision to drop the investigation into criminal association and aiding illegal migration, describing it "an additional step toward the truth." The group stated that it has always operated according to international roles.

The migrants, who were rescued off Libya in international waters, were brought to a Sicilian port last March, and the ship was briefly impounded.

The case came at a time of growing reluctance in Italy to accept migrants rescued at sea, a position that hardened after the election of a populist government.