The dollar index against a basket of currencies was last down 0.26% on the day at 92.013. The euro gained 0.27% to $1.1901 and the greenback gained 0.05% to 110.30 Japanese yen.
"Until the bond market gets the heebie-jeebies over the inflation fears again I think the long dollar position remains under assault," he said.
Treasury yields have also fallen this week after the Treasury Department saw solid demand for new sales of three-, 10- and 30-year debt on Monday and Tuesday.
More than 22 million people have had the first dose of a COVID-19 vaccine in the UK. Traders expect the swift inoculation programme will help the economy rebound from its biggest contraction in 300 years.
In early London trading, the pound rose to a two-week high against the euro at 85.57 pence. It was flat at 85.76 pence at 1227 GMT.