As Prime Minister Shinzo Abe would have it, he is not obliged to respond to criticism of the Liberal Democratic Party's 2012 draft constitution during Diet budget committee deliberations, a position that is not sitting well with the opposition.

The prime minister avoided commenting on the matter all through the Lower House meetings, which kicked off last week, and appears to be taking the same tack at the outset of the Upper House discussions that began Wednesday, where he faced off against newly elected Democratic Party opposition leader Renho.

"I'm simply dumbfounded that Prime Minister Abe, despite being head of the administration, seems to think he can decide what he should or shouldn't talk about in the legislative body" that is the Diet, Renho told reporters after the budget committee session.