The EU could not deal with a repeat of the 2015 migration crisis and must try to keep people from fleeing Afghanistan, Greece said on Wednesday, as unity between member states over deportations crumbled.
Greece last week co-signed a letter with five other EU countries saying deportations of failed asylum-seekers should continue despite the fighting between the government and the Taliban.
It said stopping the return of Afghan refugees "would send the wrong message".
"It would lead to more people trying to leave and come to the European Union," Migration Minister Notis Mitarachi told Reuters.
But two other signatories to the letter, the Netherlands and Germany, reversed course on Wednesday, saying they would not, for now, deport Afghan citizens who are seeking asylum, given the worsening conflict there.
Among other signatories, Austria said it was sticking to its position and Denmark and Belgium declined to comment.
But German Interior Minister Horst Seehofer said a state based on the rule of law had a responsibility to ensure any deportations did not put people in danger.
"The security situation is changing so rapidly that we cannot meet this responsibility," Mr Seehofer said.
Mr Mitarachi said the EU was unprepared for a repeat of the 2015 migrant crisis, when more than a million people – most of them Syrians, Afghans and Iraqis – arrived seeking refuge.
"Absolutely not. The EU is not ready and does not have the capacity to handle another major migration crisis," he said.
Last week, Germany cancelled a flight due to deport six Afghans convicted of criminal offences to Kabul because of security risks.
Fears of a new migrant crisis have increased as Taliban fighters have made sudden, strong gains in their campaign to defeat the Kabul government after the withdrawal of US-led foreign forces who had been there for two decades.
Mr Mitarachi said the EU should offer more support to help Greece's neighbour Turkey handle more arrivals from Afghanistan.
A European Commission representative said on Tuesday that it was for member states to determine their approach to deportations.
But a senior EU official said it was "hard to imagine" forced returns would go ahead in the current conditions.