The European Central Bank said Thursday it plans to purchase over €1 trillion in public and private sector bonds by the fall of 2016, a landmark decision aimed at combating stagnation and ultralow inflation in a region that has emerged as a top risk to the global economic recovery.

ECB President Mario Draghi said the ECB will buy a total of €60 billion a month in assets including government bonds, debt securities issued by European institutions and private-sector bonds. The purchases of government bonds and those issued by European institutions will start in March and are intended to run through to September 2016, Draghi said. The risks associated with the bonds of EU institutions will be shared, but purchases of other government bonds won't be subject to loss sharing, he said.