As heads of state and government jetted out of Morocco on Tuesday after formally adopting a UN deal on migration, NGOs raised doubts about its implementation on the ground and the high seas.
The Global Compact for Safe, Orderly and Regular Migration - finalised at the UN in July after 18 months of talks - was formally approved in Marrakesh on Monday in a ceremony attended by representatives of 164 governments.
A host of European politicians including German Chancellor Angela Merkel have firmly endorsed the deal, even as the US and a string of other countries have shunned it amid a wave of anti-immigrant populism.
While welcoming the agreement, the medical charity MSF and the International Federation of the Red Cross and Red Crescent (IFRC) pointed to policies by EU states that sit uneasily alongside the pact's commitments to save lives and "eradicate trafficking in persons".
"What we see right now is that months of government policies on migration are... deepening the suffering of migrants by basically offering them on a plate to criminal organisation networks," said Joanne Liu, international president of MSF.
Last week, her organisation was forced to abandon its search and rescue missions in the Mediterranean - a key crossing for migrants and refugees travelling from Africa to Europe.
The charity's vessel Aquarius has been blocked at the French port of Marseilles since losing its Panamanian registration and flag in September, amid what it has called a smear campaign led by Italy.
Both Liu and the IFRC charged that European powers have facilitated the detention of migrants in Libya.
"We have been very vocal in saying Libya is not a safe place," Liu told AFP on the sidelines of the Marrakesh conference.
But "European governments have basically been using public money to... finance detention centres in Libya."
IFRC president Francesco Rocca hit out at the EU for policies he said pushed migrants back to the highly unstable North African country, including the training of a nascent Libyan coastguard.
"Nobody should be sent back to Libya. This is unacceptable. You cannot send anyone back to a place that is not safe, and we know perfectly well that Libya is not safe," he told AFP.