A EUROPEAN court verdict that Italy breached international law by pushing back asylum seekers at sea highlights the perils of the Coalition's policy to ''turn back the boats'', the Greens and federal government said yesterday.

Italy and Australia are the most prominent countries to have implemented push-back policies to stem asylum seeker boat arrivals. Labor opposes the practice, but it is Coalition policy.

Following the ruling in the European Court of Human Rights, Italy must pay compensation of €15,000 ($18,700) to 24 Somalian and Eritrean asylum seekers who were on three boats carrying 200 people pushed back to Libya in 2009.

Amnesty International called the judgment historic. The United Nations High Commissioner for Refugees said it was ''a turning point''.

''The court's decision is yet another example of why the Coalition's inhumane and illegal policy to push back boats to Indonesia should never be applied,'' Greens senator Sarah Hanson-Young said.

A spokesman for the Immigration Minister, Chris Bowen, said: "This yet again confirms the bloody-mindedness of Tony Abbott in arrogantly spruiking a tow-back policy that our own navy says is dangerous and risks lives … and is now found to be a breach of human rights.''

The opposition's immigration spokesman, Scott Morrison, stood by the policy yesterday.