Miners helped the FTSE advance more than 80 points after three hours' trading Wednesday as fears Europe's debt crisis could hamper global growth softened.
The Dow plunged 1% in early trade today following German Chancellor Angela Merkel's warning the euro could collapse.
The US Securities and Exchange Commission (SEC) has put in place new stock trading restrictions to prevent a repeat of the Dow's dramatic plunge earlier this month.
The FTSE suffered a sharp drop in afternoon trading to close more than 3% in the red as concerns over EU debt and another Greece bomb attack rattled markets.
The FTSE was 0.9% or 50.47 points lower in early trading at 5383.26 amid fears Europe's austerity measures will slow the global recovery.
The FTSE edged higher while sterling fell from a 10-month high on the first day of the UK's new coalition Government.
The FTSE is down 2% at 5278.76 points as traders continue taking profits, paring back the benchmark's extraordinary 5.2% jump yesterday.
Profit taking saw the FTSE 100 fall 1.3% to 5316.22 points this morning, negating some of its 5.2% rise on Monday.
US stocks plunged to lows last seen in 1987 tonight, amid speculation a trader entered a "b" for billion instead of an "m" for million when placing an order.
The FTSE 100 dived 1.52% or 80.94 points to 5,260.99 with banks dragging on the index after Moody's warned UK lenders are at risk of Greek contagion.