The Liberal Democratic Party's top policymaker on Tuesday called for setting mid- to long-term time frames for raising the consumption tax beyond the current 5 percent.

"When we should hike the (consumption) tax is a point we should pay attention to," said Taro Aso, chairman of the LDP Policy Research Council. "There is a range of opinions, such as hiking the tax rate by 1 percentage point every year, or hiking it by 2 points or 5 points once every several years."

On Friday, Prime Minister Junichiro Koizumi said his administration plans to "make the consumption tax issue a subject of discussion a matter of course" when starting debate on taxation changes early this year.