Japan's prime minister said his country should be alarmed by ratings cuts in Europe and tackle the country's massive public debts to avoid becoming a next target.
Premier Yoshihiko Noda said during a live TV talk show that the eurozone debt crisis is not "someone else's problem".
Ratings agency Standard & Poor's downgraded ratings yesterday on nine eurozone countries including France, Italy and Spain.
Japan could be the next target if it is seen as dragging feet on reforms, he said.
Mr Noda reshuffled his Cabinet yesterday in a bid to win co-operation from the opposition and voters to raise the sales tax and rein in the bulging fiscal deficit.