French police officers checks a person's papers at a border post on the French-Spanish border on the A63 | GAIZKA/AFP/Getty Images EU to back temporary halt on visa-free travel Worried about a large influx from Turkey and elsewhere, EU countries will approve ’emergency brake.’

EU interior ministers are expected to approve on Friday an "emergency brake" that would allow member countries to temporarily suspend visa-free travel for non-EU citizens.

Germany and France led a push for the measure to assuage fears in national capitals that non-EU citizens could travel to the bloc in large numbers. The European Commission came up with a proposal in early May, and the national ministers will back it on Friday.

“For many member states this is a pre-requisite” for further visa liberalization, a EU official said.

There are four countries in the process of securing visa-free travel to the Schengen area: Georgia, Ukraine, Kosovo and Turkey. So in theory, 125 million people could arrive in the EU for a short visit, a prospect that terrified some member countries, who wanted a safety net.

According to the document to be approved by ministers, the emergency brake will kick in if, for example, a country tells the Commission it has faced “a substantial increase in the number of nationals ... found to be staying in the member state's territory without a right” or if there is an increase of risks to the “internal security of member states, substantiated by adequate data, in particular a substantial increase of serious crime or terrorist offenses.”

“Before it was very difficult to suspend the visa liberalization, almost impossible,” an EU official said.

The Commission will be responsible for monitoring "the appropriateness of a visa liberalization” and “will report regularly to the European Parliament and the Council at least once a year, or more frequently when necessary.”

The first country to benefit from visa liberalization is likely to be Georgia, a country of fewer than 5 million inhabitants. But the big concern is Turkey, with whom the EU struck a migration deal that promises visa-free travel for Turkish citizens if Ankara meets certain conditions.

There are almost 80 million Turkish citizens, although, according to official Turkish records, only 15.6 million of them have passports and 2.7 million of those can already travel freely. Of the remaining 12.9 million passport holders only 10 percent, according to a Commission official, have a biometric passport, which is necessary to enter the EU — that's about 1.3 million people.

Ankara had hoped to secure visa liberalization for Turkish citizens by June, instead of an earlier deadline of October, but it has not yet met all the criteria required. The Commission will publish a report on Turkish progress in mid-June.

According to an EU official, “it is a realistic estimate that it will be October” when Ankara has fulfilled all the criteria.

His reasoning is due to technical measures: even if the Commission in mid-June says that all conditions have been met, there are limited opportunities for ministers and diplomats to fill in the details ahead of a European Council on June 28. Plus, the European Parliament needs to vote on it and in July there are only a few parliamentary sessions.

"The promise that was made [of visa liberalization] was for the month of October this year," Turkish President Recep Tayyip Erdoğan said in a televised speech at the beginning of May.

That timeframe is highly unlikely to change.