Greece has rejected the reactivation of the so-called Dublin Regulation, which allows other EU member states to send refugees back to the country, a government spokesman said.
Migration spokesman Giorgos Kyritsis said on Friday that his country, which hosts a bulk of the refugees in the continent, cannot afford to take in more asylum seekers from other European countries.
"A country such as Greece which receives a large number of refugees from Turkey, and also hosts a large number of refugees - practically without any outside help - cannot be asked to receive refugees from other European countries," Kyritsis told The Associated Press. "That would be outrageous."
The Dublin Regulation that governs Europe's Schengen passport-free area stipulates that people wishing to apply for asylum must do so in the first member country they arrive in. In most cases that was Greece, whose eastern islands were overwhelmed last year by migrants packed into smugglers' boats from Turkey.
But even before last year's migration crisis, many of its EU partners had stopped enforcing the rule because Greece's asylum and migrant reception systems were below standard.
"Unless there is an effective means of redistribution across the EU, a revised Dublin system will force refugees upon receiving states closest to the external border, above all Greece, Italy and to a lesser extent Spain," Brad Blitz, migration expert and professor of international politics at Middlesex University in Britain, told the the Associated Press news agency.
READ MORE: Refugees in Greece - 'We are living in a prison here'
"That will create an ever greater strain on (Greece's) asylum system and reception capacity."
The Greek government's decision came as Athens hosted leaders of Europe's Mediterranean countries.
Greece's Prime Minister Alexis Tsipras met French President Francois Hollande, Italian Prime Minister Matteo Renzi, and leaders from Portugal, Cyprus and Malta in Athens to discuss the bloc migration and debt crises.
"Regardless of our ideological backgrounds, what unites us is our common sea, and common problems, and faith in a European vision," Tsipras said at the start of the talks.
Immigration is high on the agenda. Friday's talks are in preparation for next week's informal EU leaders' summit in Bratislava, Slovakia, as the bloc remains rattled by Britain's referendum vote to leave the EU and recent gains for the nationalist vote in Germany.