The US dollar wobbled on Thursday as the influential Chicago purchasing managers' index disappointed.

The regional index of business activity fell more than expected, to 61.2 in December from 65.2 in November. The slide in the employment component to 49.1, below break-even of 50, from 60.8 in November, was particularly important, according to Kamal Sharma, currency strategist at Dresdner Kleinwort Wasserstein.