Pound falls on weak UK economic data
The pound fell against other currencies following the release of weaker-than-expected UK economic data.
Official figures showed industrial output fell by 0.7% in February from the month before, while construction output shrank by 1.7%.
Separate data showed the UK's deficit in goods and services widened to £3.7bn in February, from £3bn in January.
Elsewhere, stock markets remained wary following news of the US missile attack on a Syrian government airbase.
Worries over disruption to oil supplies in the Middle East sent Brent crude 0.5% higher to $55.14 a barrel.
Gold - traditionally seen as a haven asset in times of uncertainty - rose 0.5% to $1,252.50 an ounce.
The rise in the gold price sent shares in Randgold Resources up 4.3%, making it the biggest riser on the FTSE 100.
London's benchmark share index ended the day up 46.1 points, or 0.6% at 7,349.3.
Shares in Sainsbury's rose 2.9% while Tesco was 2.4% higher after UBS assigned a "buy" rating to both of the supermarkets.
However, in the FTSE 250, shares in Ocado fell 4.6% after UBS cut its rating on the online grocer to "sell" from "buy".