The Organization for Economic Cooperation and Development on Wednesday upgraded its growth outlook for the economy for 2015 and 2016, aided by lower oil prices that are expected to boost global demand.

In its interim economic assessment report, the Paris-based organization said Japan's economy is now expected to expand 1 percent this year, revised up from its November forecast of 0.8 percent, and grow 1.4 percent in 2016, up from the previous estimate of 1 percent.

"Demand will be lifted by the fall in oil prices, the fiscal stimulus package for 2015 and the announced continuation of monetary easing measures," the OECD said in the report.