The Simon Wiesenthal Center on Sunday gave Germany and the United States top marks for pursuing and prosecuting Nazi war criminals but slammed Australia, Canada and several former east-bloc countries for "complete failure" to bring suspects to justice.

In an annual report released on the eve of Israel's Holocaust remembrance day, the Los Angeles-based Jewish organisation said that contrary to widely held belief it is still not too late to apprehend and try Nazis.

"It is clear that at least several such criminals will to be brought to trial during the coming years," wrote the report's author, the centre's Israel director, Efraim Zuroff.

"While it is generally assumed that it is the age of the suspects that is the biggest obstacle to prosecution, in many cases it is the lack of political will, more than anything else," he said.

The report said the most disappointing case was that of Sandor Kepiro, convicted by Hungary of helping to organise the 1942 murder of at least 1,200 civilians in Serbia but never punished, although the centre has located him in Budapest.

The report listed Estonia, Lithuania and Ukraine along with Australia, Canada and Hungary as countries "in which there are no legal obstacles to the investigation and prosecution of suspected Nazi war criminals, but whose efforts (or lack thereof) have resulted in complete failure during the period under review."

Germany and the United States were the only countries the report gave an "A" grade for their "highly successful investigation and prosecution programme."