Group of Seven (G7) leaders agreed on Friday that they will aim for the Paris climate agreement to go into effect by the end of the year, a Japanese senior government spokesman said.

"G7 countries need to work together and spearhead effort toward the early entry into effect and effective implementation of the historic Paris accord," Deputy Chief Cabinet Secretary Hiroshige Seko quoted Japanese Prime Minister Shinzo Abe as telling other G7 leaders.

Last December in Paris, almost 200 nations agreed a sweeping plan to end global dependence on fossil fuels to limit rising temperatures.