EU foreign ministers warned Turkey on Monday to show restraint in its response to a failed military coup, worrying that Turkish retaliatory measures are going too far.
Punishment against the coup plotters must not include "measures that could lead to an authoritarian state," French Foreign Minister Jean-Marc Ayrault told journalists in Brussels ahead of talks with his EU counterparts.
The coup attempt on Friday night by a group within the Turkish armed forces left 290 people dead - including more than 100 alleged mutineers - and more than 1,100 injured.
President Recep Tayyip Erdogan has blamed Fethullah Gulen, a US-based, Turkish-born preacher and one-time ally turned rival accused of running a "parallel state."
Thousands of people have been arrested since the foiled coup. Arrest warrants were also issued for 250 judges and prosecutors, while 2,745 judges were dismissed from their posts over the weekend.
"This is a reaction that is not in line with rule of law," Luxembourg Foreign Minister Jean Asselborn said.
The European Union's commissioner for neighbourhood policy, Johannes Hahn, suggested that the Turkish government had long been planning action against opponents.
"That the lists are available already after the event indicates that this was prepared, that at a certain moment it should be used," he said in Brussels.
Hahn added that the arrests of judges was "exactly what we have feared" and that international standards on the rule of law have not been "really met" in the response to the coup.
Many of the ministers gathered expressed concern about the retaliation against the judicial officials, as well as about calls in Turkey for a reintroduction of the death penalty.
"Today we will say together with the ministers that this [coup] obviously doesn't mean that the rule of law and the system of checks and balances in the country does not count," EU foreign policy chief Federica Mogherini said.
"It's very important ... that we see restraint and moderation on all sides," added Britain's new foreign secretary, Boris Johnson.
The EU ministers were meeting with US Secretary of State John Kerry Monday to coordinate their responses.
Hahn and Mogherini had expressed their "full support to the [Turkish] democratic institutions" in a joint statement issued on Saturday, but had underlined too "the need for a swift return to Turkey's constitutional order."
Erdogan has also raised eyebrows in the EU with suggestions that he will consider the possibility of capital punishment for those who carried out the failed coup attempt.
The death penalty has not been used in Turkey since 1984 and was abolished in 2004. The 28-country EU is a lead campaigner for its abolition around the world.
"This poses a problem in the relations with the EU. We cannot imagine this from a country that wishes to get closer to the EU," Belgian Foreign Minister Didier Reynders said in Brussels. "So we will have to be very firm today."
Asselborn had earlier told the German broadcaster ZDF that the reintroduction of the death penalty in a country seeking to join the EU would leave the membership negotiations "choked." Turkey has been an EU candidate since 1999.