The FTSE was up in early trading as investors responded positively to Chinese manufacturing figures.
Meanwhile the equivalent UK figures, released this morning, show that British manufacturing activity shrank much less than expected in November.
Despite this, concerns over the US "fiscal cliff" - a combination of US government spending cuts and tax rises due to be implemented in early 2013 - could stop the index moving much higher.
London's blue chip index gained 9.3 points – or 0.3 per cent – to hit 5,876 this morning.
Fund management group Schroders was the top-performing FTSE 100 stock, rising 3.6 per cent after Bank of America Merrill Lynch upgraded the stock to "buy" from "neutral."
Publisher Reed Elsevier was close behind, adding 15p – or 2.4 per cent – to hit £6.57 a share.
Miners were buoyed by the data from China, the world's top metals consumer, with Vedanta, Kazakhmys, ENRC and Rio Tinto all benefiting.
Polymetal was also up 0.5 per cent after saying that gold reserves at one of its Russian mines are twice as large as previously thought.
Insurer RSA gained after Deutsche Bank upgraded the stock to "buy".
But there were few fallers on the FTSE 100 this morning, with Hargreaves Lansdown posting the largest drop of 1.4 per cent.
In the FTSE 250 Cable & Wireless Communications added 5.4 per cent after agreeing to sell most of its Monaco & Islands division to Bahrain's Batelco Group in a deal worth up to $1bn.
Asian stocks struggled overnight, with the Hang Seng down 1.2 per cent and the Nikkei up just 0.1 per cent.