Updated 12.30pm: The FTSE plunged in midday trade after Chancellor George Osborne unveiled details of the coalition government's £6.2bn spending cuts.
US markets plummeted almost 4% yesterday as the fallout from the eurozone crisis continued to escalate.
The FTSE closed on Thursday deep in negative territory after German Chancellor Angela Merkel stepped up calls for tougher regulation of banks and financial markets.
Markets are again seeing a volatile trading day following Germany's ban on naked short-selling in European public debt, as well as shares in the country's 10 largest financial institutions.
Miners are among the early fallers on the FTSE as European markets tumble following a ban on naked short-selling in Germany.
On another volatile day for global markets, Investment Week keeps you up to date with all the changes across the asset classes.