US markets opened lower this afternoon, following falls across Europe today as fears of a Greek default resurfaced once more.
Major European and US indices have dropped as the ECB revealed a key official was stepping down.
UK shares were muted at the open, failing to take advantage of yesterday's 3% rise in the S&P 500.
US markets opened sharply lower on Tuesday, having missed the sell-off at the start of the week, before services data helped improve sentiment.
US markets have opened lower as investors take a dim view of Hewlett Packard's latest acquisition and send its shares down 20%.
US manufacturing data has sent markets plunging again, with the S&P 500 down 4.5% and the UK and Europe also tumbling.
US investors jettisoned shares in early trading following a warning from consumer giant Walmart, piling on the pressure following weaker than expected German economic growth.
GMO's Jeremy Grantham has said the S&P 500 is still heavily overvalued, and "worth no more than 950".