At last, some respite for the beleaguered US Treasuries market. On the eve of the Group of Eight finance ministers' meeting this weekend, Kaoru Yosano, Japan's finance minister, said his faith in US government bonds was “absolutely unshakeable”. The market reaction was swift. Yields on the benchmark 10-year bond fell some 6 basis points to 3.8 per cent.

Given that Japan is the world's second biggest owner of Treasuries, Mr Yosano may have been talking his own book. Still, it was a happy coda to a difficult week for US debt markets. At one 10-year auction this week, Treasury yields rose to 3.99 per cent, their highest this year.

Given that the US may have to issue some $3,250bn of bonds this year, this increased worries that the US could face a buyers' strike, especially by foreign central banks, among its biggest purchasers.