Most Frontex deportations to take place from Germany, Italy

The flights are part of wider push to get EU states to use Frontex to help return rejected asylum seekers and others ordered to leave.

Some 340,000 return decisions were issued last year. But with a return rate at 21 percent, EU states are also not demanding enough readmission requests from countries of origin, EU home affairs commissioner Ylva Johansson told reporters in Strasbourg, earlier this week.

"We need to step up on the readmission requests," she said.

Johansson made similar comments earlier this year amid plans to leverage visa restrictions on origin countries that do not take back their nationals. That leverage is encoded in article 25a of the EU's visa law.

"One of the most important reasons behind the low EU return rates is the lack of third country cooperation," said Maria Malmer Stenegard, Sweden's migration minister.

These issues are not new.

EU and African leaders, for instance, were already at loggerheads over returns and readmission in 2015 at the Valletta Summit in Malta.

Aside making promises to work more closely together on return, readmission and reintegration, the 2015 summit had also made statements to tackle migrant smuggling.

What is new is that Frontex, a Warsaw-based agency, has had its mandate reinforced and is now set to spend some €100m this year alone on returns.

The European Commission is also banking on a police database known as the Schengen Information System (SIS) to help.

The system, which contains biometrics, starting issuing alerts on return decisions. "That means that we will have a much better position to carry out the mutual recognition of return decisions," said Johansson.

Such mutual returns could put a strain on bilateral diplomatic relations between a member state and an origin country.

But Frontex has since been deployed to Moldova, North Macedonia, Albania and Montenegro.

And plans are underway for similar deployments in Mauritania, Niger, Senegal and elsewhere, posing questions on accountability and human rights oversight.

The plans are not well received and have come to a standstill in Mauritania and Senegal. Authorities in Senegal worry the agency will breach human rights, given its legacy of abuse in the EU.

Last July, the commission had also announced new anti-smuggling partnerships with Morocco and Niger. This was followed by internal briefings that the EU wants to shore up police investigations in Niger.

It plans to do the same with Tunisia and Egypt.

Meanwhile, people with return orders in the EU at risk of absconding could also end up being detained.

In a recommendation, attached to pre-existing EU rules on return, the commission offered several alternatives to detention.

This includes requiring people to report daily to the police, surrender their passports, deposit a sum of money, as well as "the use of innovative technology."