The Citizen Protection Ministry reported Tuesday that the fence, which would be three metres tall, would be finished by April near the Evros river and town of Orestiada. Greek officials have said that is a weak point in the border prone to illegal crossings.

That is still a significant step-down from plans mooted over the weekend for a 206-kilometre-long fence.

Greek media has ridiculed the plan, noting that a 12.5-kilometre long fence is unlikely to be much more than window dressing for the problem of illegal immigration into Greece. European officials have suggested Greece would be better served by overhauling its asylum system, not building walls.

Opposition politicians also piled on, with some saying walls will not solve the problem, and others urging the Greek government to help the illegal immigrants on their way to Central Europe, where most are likely headed anyway, they said.

But the official who has pushed the idea rejected all criticism Tuesday.

'It is duplicitous that the same people who accuse Greece of not living up to its obligations under the Schengen agreement are now criticizing it because it is trying to strengthen its borders,' said Citizen Protection Minister Christos Papoutsis.

And some conservative Greek media outlets have praised the government for trying to address the migration problem.

In the six months up through the end of November, 33,000 illegal immigrants were detected crossing the Greek-Turkish land border. Most were from Afghanistan, Algeria, Pakistan, Somalia and Iraq. Since November, European Union teams have been patrolling the border with Greek police.

It is the first time that an EU Rapid Border Intervention Team (RaBIT) has been deployed to an EU member state by the bloc's frontier agency, Frontex, since the teams were created in 2007.

Officials said over the weekend that, in 2010, an average of '200 refugees each day' had crossed into Greece from Turkey.

Around 80 per of the illegal immigrants in the EU arrive via Greece. Large numbers then seek to reach Italy via ferry.

There are currently an estimated 300,000 people living illegally in Greece.

Illegal immigrants nabbed by border police are placed in detention camps, which are bursting at the seams. Human rights groups have criticized Greece's asylum policy and conditions in the camps.