0315 GMT February 25, 2020
Forty-one people were finally allowed to step off migrant rescue charity Mediterranea's Italian-flagged Alex, which arrived at the port on Saturday in an overnight operation that saw the ship temporarily seized by authorities, AFP reported.
The boat's captain Tommaso Stella is being investigated for allegedly aiding illegal immigration, according to the Italian news agency Agi.
It is the second vessel in just over a week to defy Salvini's attempts to block Italian ports to rescue ships, as tensions increase over the international response to the migration crisis.
A third boat that had also been waiting off Lampedusa, the German charity Sea-Eye's vessel Alan Kurdi carrying 65 migrants, was sailing toward Malta on Sunday, even though it has not received permission to enter Maltese waters.
The charity said it could not "wait until the state of emergency prevails" in a message on Twitter.
"Now it has to be proven whether the European governments stand by Italy's attitude. Human lives are not a bargaining chip," it added.
Salvini last month issued a decree that would bring fines of up to 50,000 euros ($57,000) for the captain, owner and operator of a vessel "entering Italian territorial waters without authorization".
After the Alex reached port, the deputy prime minister said that he would raise the maximum fine to one million euros.
"I do not authorize any landing for those who couldn't care less about Italian laws and help the people smugglers," Salvini tweeted late Saturday.
Mediterranea said it had sailed to "the only possible safe port for landing", citing "intolerable hygiene conditions aboard" in a tweet Saturday.
Libya, which has been wracked by chaos since the 2011 uprising that killed former leader Muammar Gaddafi, has long been a major transit route for migrants, especially from sub-Saharan Africa, desperate to reach Europe.
On Tuesday night, 53 migrants were killed in an airstrike on a detention center in a Tripoli suburb held by forces loyal to the UN-recognized government.
Pope Francis on Sunday called for "humanitarian corridors" to help rescue migrants in response to that airstrike.
Also on Sunday, Maltese authorities said they had rescued another group of 50 migrants in Malta's search and rescue zone on Sunday, after receiving a distress call saying their vessel was sinking.