Harry Sissen: Denied the charges

During the four-week trial Mr Hague also revealed that Sissen had confessed to him that he had smuggled rare birds into Britain on a previous occasion.

Customs and Excise officials and conservationists gave evidence, stressing that this was the biggest case in British legal history concerning the smuggling of rare species.

The jury returned its verdict after seven and a half hours deliberation, convicting Sissen on four counts of smuggling.

The Lear's macaw originates from a small corner of north east Brazil and is rarer than the Giant Panda, Tiger and Black Rhino.

The birds, which have been kept at a secret location while the case was being brought to court, will now be returned to Brazil where the government is to oversee their return to the wild.

According to Customs officer Rob Hastings-Trew, the birds had endured a long journey before their arrival in Britain.

Speaking after the case, he said: "They were originally captured in Brazil and taken to Yugoslavia where we believe Harry Sissen purchased them.

"They then travelled back across several frontiers before finally being brought into the UK through Dover."

RSPB investigations officer Duncan McNiven added: "This is an important verdict in the most serious case of endangered species smuggling ever to be brought before a British court.

"Mr Sissen acted with a total disregard for the critical situation which this species faces in the wild and his selfish actions have helped to edge this beautiful parrot closer to extinction."