Cheer over America’s fiscal cliff deal sent the FTSE 100 Index soaring past the 6000 mark for the first time since July 2011 in a global shares rally.

Markets worldwide powered ahead after US politicians passed short-term measures to stave off devastating automatic tax hikes and spending cuts that had threatened to derail the world’s biggest economy.

The FTSE 100 surged 2.2% ahead, closing 129.6 points higher at 6027.4, while the Dow Jones Industrial Average on Wall Street leapt 1.7% higher shortly after opening.

There were similar share gains across Europe, with Germany’s Dax up by more than 2% and France’s Cac 40 2.6% higher.

A surprise boost for Britain’s manufacturing sector added to the rally in London after a closely-watched survey revealed a return to growth in December.

The latest Markit/CIPS purchasing managers’ index (PMI) showed a headline reading of 51.4 in December, marking the highest for 15 months and the survey’s first indication of increased activity since March.

In London, banks and miners were among those leading the FTSE 100 higher after the passing of a new bill by Congress on Tuesday night averted widespread tax increases and delayed spending cuts by two months.

Meanwhile, the US dollar weakened against major currencies as traders moved to reverse their recent flight to the safe haven of the greenback.

Sterling rose to $1.63 dollars, while it also strengthened to 1.23 euros.

The biggest FTSE 100 risers were Evraz up 18.7p to 277.6p, Glencore International ahead 25.2p to 376.5p, Xstrata 70.5p higher at 1129.5p and Eurasian Natural Resources up 18.6p at 302.6p.

The only FTSE 100 fallers were Sainsbury’s down 9.1p to 336p, Morrisons off 5.6p to 257.4p and British American Tobacco off 30p to 3091p.