Prime Minister Naoto Kan kicked off the year by sacking his right-hand man, Chief Cabinet Secretary Yoshito Sengoku, and appointing a one-time critic of him in Kaoru Yosano to the Cabinet, reaching out to the opposition to gain support for the fiscal 2011 budget.

But his moves appear to have backfired, with opposition parties ready to jump on Kan over the controversial appointment of the former Liberal Democratic Party heavyweight as state minister in charge of economic and fiscal policy.

"We will grill him in the Diet," Ichita Yamamoto, the LDP's policy chief in the Upper House caucus, said on Jan. 15, adding that he personally favors submitting a nonbinding censure motion against Yosano in the upper chamber.