Speaking in Berlin on the eve of the Group of Eight talks in Italy, Mr Rudd joined British counterpart Gordon Brown to argue that it is too early for industrialised nations to pull back on fiscal stimulus measures.

"As we move from the first phase of the financial crisis into the second, we must remember that the challenge of recovery could be at least as great as the challenge of the crisis itself at its absolute height at the end of 2008," he warned.

Mr Rudd was visibly moved when he paid a visit to Berlin's Memorial to the Murdered Jews of Europe, a haunting maze of thousands of concrete pillars.

Walking through the 2711 concrete slabs, he said any reminder of the enormity of the Holocaust "takes your breath away". "Any human being responds from the pit of their stomach. This is a very sober and sombre place and may it never happen again."

He also visited the Berlin 1939-1945 war cemetery before holding meetings with German President Horst Kohler and Chancellor Angela Merkel.

He told German and Australian business leaders that, while trade, industrial output and stockmarket statistics during the Great Depression can be compared with those of the global credit crisis, the world had until now avoided the long-term decline of the 1930s because of the co-ordinated policies of the G20 governments.

Meanwhile, Tim Fischer, Australia's ambassador to the Holy See and former Coalition deputy prime minister, has defended Mr Rudd's right to make representations for Mary MacKillop to be made a saint when he meets the Pope tomorrow.

Catholic Liberal frontbenchers have strongly attacked his planned intervention. But Mr Fischer said it was "entirely appropriate".

With MICHELLE GRATTAN