“Zhu Guangyao, vice-finance minister, told a media briefing that China has made clear its unease over the political impasse in Washington. In Japan, the Ministry of Finance is very worried about the potential impact on currency markets, according to a senior official. A US default could cause investors to dump the US dollar, which would sharply push up the value of the yen.”

Source:China and Japan warn US on default – FT.com