The focus on security in the aftermath of the Sept 11 attacks in the United States has led to perhaps the worst marginalisation of human rights in Asia in decades, Human Rights Watch said in its annual report.

The United States came in for particular criticism for its willingness to overlook human rights abuses in a bid to bring Asian governments on side in its ongoing war against international terror.

"When the planes crashed on Sept 11, they drove a large hole through the region's fragile human rights architecture," the New York-based rights watchdog said in its 30th annual report.

"Perhaps more broadly than anywhere else in the world, the United States muted its criticism of opportunistic repression in Asia so as not to offend governments otherwise cooperating in the war."

Many of the region's governments that sought to implement policies restricting human rights took advantage of the new political space provided by the war on terror, the report found.