A government panel kicked off a seven-day discussion Monday on whether the sales tax should be hiked next April amid concerns it could derail Prime Minister Shinzo Abe's radical efforts to end decades of deflation.

Abe is soliciting opinions from 60 people ranging from university professors and business leaders to heads of non-profit organizations so he can decide whether the first phase of the tax hike, to 8 percent from 5 percent, should proceed next April.

Abe is expected to make his decision before leaving for the Asia-Pacific Economic Cooperation forum summit on Oct. 7. It will be based on revised figures for April-June gross domestic product, which will be announced Sept. 9, and the panel's opinions.