Germany's push for fiscal austerity is preventing the euro zone economy from growing—and instead, the region's debts should be written off in a "modern-day debt jubilee", a leading professor told CNBC on Monday.

"If you have got the private sector paying its debt down and you tell the government to do the same thing, you are saying 'hey guys, let's shrink the amount of money in the economy, and see if you can grow'," Australian economist and author Steve Keen said on Monday.