After jumping 2.5% on Thursday, the FTSE 100 index closed up 83.2 points, or 1.4%, at 6,096.01.
Mining shares bolstered the index as commodity prices rallied. Anglo American rose 7% and Glencore was 7.5% higher.
But shares in Royal Bank of Scotland dropped 7% to 226p after the bank reported yet another annual loss.
RBS reported a loss of £1.98bn for 2015, partly as a result of putting aside £3.6bn for litigation costs.
Stripping out one-off costs, RBS recorded a £4.4bn underlying profit, although this was down from £6bn a year earlier.
Sports Direct shares also fell, down 0.5%, after the retailer said its borrowing costs were set to increase.
The company said it would stop using a loan facility supplied by founder Mike Ashley, which charges lower rates.
Shares in British Airways owner IAG fell 3% despite the airline group reporting a big increase in annual profits.
On the currency markets, the pound fell 0.65% against the dollar to $1.3871, but rose slightly against the euro to €1.2685.
(Close): The London market continued to rally, but shares in RBS sank 8% after it reported another annual loss.