ATHENS – With more than 64,000 refugees and migrants abandoned in Greece after the European Union closed its borders to them, the former head of the country’s asylum service said only 16 percent can be sent back to Turkey under a suspended swap deal.

“Given what we know about Turkey, those who can be shipped back are mostly Syrians, who enjoy a high level of protection,” Maria Stavropoulou told Kathimerini, adding that the agency ruled that 2,200 Syrians can be returned from Greece to Turkey on safe third country grounds.

“However, due to appeals and cancellation requests the process can take a very long time,” she said. There are more than 15,000 on Greek islands, sent there by human traffickers Turkey has allowed to operate even during the suspended deal that began almost three years ago and has floundered amid penetrating criticism from human rights groups.

Stavropoulou, whose second term in office expired earlier in February, said authorities have recorded a drop in the number of arrivals in categories that are not eligible to return to Turkey or to their countries of origin.

“Most people who land on the islands come from countries with high recognition rates such as Syria, Iraq and Afghanistan,” she said, a mix of those fleeing war and strife and others hoping to get to more prosperous EU countries in search of work and a better life.

According to a March 2016 deal signed by the EU and Turkey to stem the flow of migrants in the Aegean, Turkey would receive up to six billion euros in aid, visa-free travel to Europe for Turkish citizens and renewed EU accession talks in return for agreeing to take back those who cross over to Greece.

The slow pace of returns is often blamed on the huge backlog, which Stavropoulou puts at 9,000 cases.

“If (migrant) flows toward the islands came down to zero, I believe that the process could be completed in up to two-and-a-half months,” she told the paper, adding that there’s been an increase in the number of Turks who fled that country in the wake of President Recep Tayyip Erdogan’s purge of society after a failed coup attempt against him in July, 2016.

A total of 1,800 Turkish nationals applied for asylum in Greece in 2017, the service said but they are in the long queue that swelled with Greece unable to process the asylum applications faster and complaining of too little help from the EU even though a Greek politician, New Democracy’s Dimitris Avramopoulos, is head of the migration service for the bloc.