The EU on Wednesday gave conditional backing to visa-free travel for Turks and unveiled an overhaul of its asylum system under which member states that refuse to take a quota of refugees will be fined.
The European Commission further announced an extension of border controls in the passport-free Schengen zone as it steps up efforts to tackle the biggest influx of migrants and refugees since World War II.
Turkey has threatened to tear up the March agreement to take back migrants who cross the Aegean Sea to Greece if the EU fails to keep its promise to allow Turkish citizens to travel without visas to the Schengen area by the end of June.
"The European Commission is today proposing... to lift the visa requirements for the citizens of Turkey" on condition that Ankara fulfils "as a matter of urgency" criteria set by the EU, according to a document tweeted by Competition Commissioner Margrethe Vestager.
The step must now be approved by all 28 EU member states and the European Parliament.
"The EU must stick to its promise," Turkish Foreign Minister Mevlut Cavusoglu said in televised comments on Wednesday.
"Our citizens deserve visa-free travel. We are about to complete the technical work including passport, we would like to see this in the EU Commission's report. If there is any shortcoming, it can be overcome with Turkey's determination," he said.
The Commission found that Turkey has still failed to achieve all 72 visa benchmarks, which range from biometric passports to respect for human rights, meaning its approval will be conditional on Ankara fulfilling them all.
Brussels also overhauled its outdated asylum system with a mechanism for relocating refugees, with states that decline to take their quota facing a fine of 250,000 euros ($290,000) for each person refused.
The changes are designed to more fairly share responsibility for migrants and refugees arriving in Europe.
The so-called Dublin rules currently in force have been criticised as obsolete and unfair to countries like Greece, where most of the migrants entered the bloc last year.
Under those rules, migrants seeking asylum must lodge their application in the country where they first arrived, and should be returned there if they try to move elsewhere in the bloc.
The Commission is proposing a special mechanism whereby refugees and migrants can be relocated to other countries if a crisis is declared -- for example in Greece.
The Turkish deal is the cornerstone of the EU's plan to curb a crisis that has seen 1.25 million Syrian, Iraqi, Afghan and other migrants and refugees enter since 2015, largely through Greece, although the numbers of arrivals have dropped since March.
Many EU states still have concerns about the legality of the deal and the human rights situation in Turkey, where an increasing number of journalists and critics of President Recep Tayyip Erdogan have been prosecuted.
The plan for 90-day visas must be cleared by all 28 nations in the bloc as well as the European Parliament.
EU vice president Frans Timmermans said Brussels had "absolutely not" been too soft on Ankara.
Turkey has been rushing through laws in recent days to meet the EU requirements, although that effort has occasionally stalled because of a series of mass brawls in parliament.
The EU will furthermore allow countries to extend border controls in the Schengen area as a result of the migrant crisis and recent terror attacks.
Germany, France, Austria, Denmark and Sweden requested the extension, saying the border situation remains "extremely volatile".
Since 2015 several countries in the 26-nation Schengen zone have reintroduced border controls due to the migrant crisis -- effectively suspending its principle of border-free travel.
European sources said the Commission was to approve the measure in line with its so-called "roadmap" for the restoration of the normal functioning of Schengen "by the end of the year".
EU rules say countries can reintroduce border controls for up to two years, in periods of up to six months at a time, in exceptional circumstances.