Australian Immigration Minister Peter Dutton said on Thursday that new border controls enacted in December 2013 have led to turning back 20 boats at sea, preventing at least 633 people "from arriving in our country."

"The fact that today we celebrate that we have not had a successful people smuggling venture in a year, and that over the course of the last 18 months or so we have turned back 20 boats and stopped 633 people from arriving in our country, is a significant achievement," Dutton said.

The immigration minister added that if the boats were not prevented from landing ashore, hundreds or thousands more "would have followed them."

"We have a very clear policy in place and that is that people who seek to come to our country by boat illegally will not settle in our country," Dutton said.

Controversial policy

Australia's controversial turn-back policy for asylum seekers has been widely criticized by the UN and human rights organizations.

However, Prime Minister Tony Abbott - who has vowed to strengthen immigration restrictions - continues to defend the policy.

In March, Abbott decried the UN, saying that "Australians are sick of being lectured to by the United Nations, particularly given that we have stopped the boats."

The military-led Operation Sovereign Borders, which blocks asylum seekers and migrants from reaching the Australia's shores, has come under increased scrutiny in recent months.

Paying off smugglers?

In June, reports emerged that Australian military personnel provided crewmembers of a boat carrying asylum seekers $5,000 (4,452 euros) each to return to Indonesian waters, prompting a diplomatic rift between Jakarta and Canberra.

Abbott neither confirmed nor denied the charges, sidestepping allegations that his government was endangering lives at sea.

Abbott's conservative government, which came into power in September 2013, has vehemently defended the stern border controls as a response to the former Labor government, which witnessed thousands of asylum seekers arrive boat and hundreds killed en route.

ls/jil (AFP, dpa, Reuters)