Council of Europe report alleges NATO warships did not come to aid of migrants feeling conflict adrift in Mediterranean.

A European rights watchdog has condemned NATO and Western navies for allegedly not coming to the aid of a boat full of migrants adrift in the Mediterranean Sea during last year's military campaign against Libya.

A committee of the Council of Europe said in a report on Thursday that 63 of the 72 people on board perished when the boat was allowed to drift for weeks after its engine failed. It received no assistance during this time.

The report accuses NATO of not being "very approachable with regard to requests for search and rescue operations".

NATO warships and support vessels were patrolling the area at the time, enforcing an arms embargo against Libya as part of a UN resolution.

The alliance has said its ships rescued hundreds of people in their area of operations.

'Shocking' findings

The report, entitled "Lives lost in the Mediterranean Sea: who is responsible?" was released by the Parliamentary Assembly of the Council of Europe (PACE), following a nine-month long inquiry.

It was conducted after the March 2011 incident, in which it is alleged that the migrants, who were attempting to flee the conflict that resulted in the overthrow of Muammar Gaddafi, died at sea after having their appeals for rescue ignored.

Tineke Strik, the rapporteur for PACE, said she was "shocked" by the findings of her inquiry.

"Since the beginning of 2011 at least 1,500 people are known to have perished in the Mediterranean trying to reach European soil - despite this being one of the busiest and best-monitored seas in the world," she said in a statement.

"My inquiry has focused on one particularly tragic incident, in which 63 people died, to try to establish who bears responsibility for their deaths. I have been deeply shocked by what I have learned."