The captain of a Spanish charity ship carrying 134 rescued migrants warned Friday of the "explosive" situation on board the vessel anchored within swimming distance of Italy's Lampedusa island but forbidden to approach.
Italy has evacuated a handful of medical cases from the Open Arms but far-right Interior Minister Matteo Salvini has been refusing to allow the vessel to dock despite a European deal to take in those remaining.
The captain of the ship operated by Proactiva Open Arms, Marc Reig, said that those on board, rescued after leaving chaos-stricken Libya, were "broken psychologically".
"Every second that passes, the bomb ticks a second closer. Either someone cuts the red cable and defuses this bomb now, or the Open Arms will explode," he told Spain's TVE television.
"This is inhuman. We're close to land and people could swim there. They want to throw themselves in the water. It's untenable. They can't take it anymore."
This is the umpteenth standoff between a charity vessel rescuing migrants making the perilous journey across the Mediterranean and Salvini, but this time set against the background of a political crisis in Rome.
Thursday saw sparring between Prime Minister Giuseppe Conte and Salvini, who last week pulled his party out of the ruling coalition in the hope of toppling the 14-month-old government.
Salvini's anti-immigrant League party has been squabbling with coalition partner the anti-establishment Five Star Movement (M5S) over a host of issues.
"France, Germany, Romania, Portugal, Spain and Luxembourg have told me that they are ready to welcome the migrants," Conte said in an open letter to Salvini, who has sought to bar all NGO rescue vessels from entering Italian waters.
In a distinct change of tone since the coalition disintegrated last week, Conte slammed what he called Salvini's "obsessive focus" on an immigration policy reduced to the phrase "closed ports".
Salvini says that Italy bears an unfair burden as the first port of call for refugees crossing the Mediterranean.
Responding to Conte, Salvini wrote on Facebook: "It is clear that without (my) resolve, the European Union would never have lifted a finger, leaving Italy and the Italians on their own like (previous governments) did for years."
The UN refugee agency welcomed the news of a deal to distribute the migrants but regretted it took so long.
"People cannot be left at sea for days on end. Predictable, regional and fair approach urgently needed so no rescued person is again left at sea for so long," the UNHCR tweeted.
- 'Listening to my conscience' -
After Salvini pulled the plug on his coalition with M5S last week, he had hoped for a immediate no-confidence vote but his gambit failed.
The fate of the migrants aboard the Open Arms vessel is now at the centre of Italy's political crisis.
Earlier this month, Salvini signed a decree banning the Open Arms from Italian waters, saying it was to protect public order.
But Proactiva appealed to an administrative court which on Wednesday suspended his decree.
Salvini then signed a new one blocking the ship, but in a demonstration of his diminished power, Italy's defence minister blocked it on Thursday.
Elisabetta Trenta, an M5S party member with the authority to sign off on Salvini's decree, announced that she decided not to do so after "listening to my conscience".
It is estimated Salvini enjoys up to 38 percent support among the electorate, thanks largely to his hardline against immigrants.
Spokeswoman Vanessa Mock said the European Commission welcomed the willingness of member states to help relocate the migrants.
The Commission is ready to help "once a solution has been found for the disembarkation of the persons rescued at sea. The situation where persons are stranded at sea for days and weeks on end is untenable."
The mainly African migrants aboard Open Arms had been plucked from boats in the Mediterranean this month, with weather conditions encouraging more departures from Libya.
Another rescue ship, the Ocean Viking, operated by SOS Mediterranee and Doctors without Borders (MSF), is also looking for a port to dock with more than 350 migrants on board.