The agreement seeks to wean the world economy off fossil fuels in the second half of the century, limiting the rise in average world temperatures to "well below" 2.0 degrees Celsius (3.6 Fahrenheit) above preindustrial times.
The delay in ratification could limit Japan's ability to influence negotiations on the finer details of the agreement. Those talks were set to formally begin during the COP-22 meeting in Morocco that started on Monday.
Representatives from nearly 200 countries convened in Marrakesh, Morocco for two weeks to discuss the nuts and bolts of the Paris accord and the policies, technology and finance needed to ensure the Paris goals are achieved.
"Japan aims to play a leading role in crafting arrangements that raises transparency in each country's emission cuts to help accomplish the spirit of the Paris agreement," Japan's Prime Minister Shinzo Abe said in a statement on Tuesday.
Backing for the accord from several European nations, Canada, Bolivia and Nepal last month pushed the agreement past the 55 percent of emitters limit needed for implementation, with U.S. President Barack Obama calling for other nations to sign up "as soon as possible."
The agreement is meant to cut global greenhouse gas emissions, mainly from burning fossil fuels, to limit floods, droughts, more powerful storms and rising ocean levels.
Japan has also been criticised for pressing ahead with plans to open scores of new coal-fired power plants at home and as Prime Minister Shinzo Abe's government pushes coal burning power technology abroad.