Sterling hit a five-year high on Monday as data from the UK's manufacturing sector came in stronger than expected.
Macro data was at the forefront of investors' minds this week, after a surprise drop in UK inflation sent the pound lower.
Sterling rose to its highest level in nine months against the US dollar as the US government slipped into a partial shutdown.
The FTSE 100 index was in the red just after midday, dragged down by mining stocks which sold-off as oil and metals prices weakened.
Hargreaves Lansdown's legal challenge to HMRC's move to tax platform rebates was the story of most interest to Investment Week's readers this week.
Sterling has risen to a seven-month high against the dollar after the UK's unemployment rate unexpectedly dipped from 7.8% to 7.7%.
Sterling dropped and then recovered sharply minutes after new Bank of England Governor Mark Carney told the world he has no plans to raise rates any time soon, but was upbeat on UK growth.
The FTSE 100 closed 1.4% down on Wednesday after new Bank of England Governor Mark Carney gave the market forward guidance, but sterling recovered after an initial drop.
The pound has slid sharply over the last few weeks versus a basket of currencies, while the US dollar has continued its 2013 resurgence, but where are the screaming buys in currency markets now?