* Miners in demand; Fresnillo gains on upgrade

* Banks firmer; Bank of England decision awaited

* Defensive issues weak led by drugs, tobaccos

By Jon Hopkins

LONDON, July 9 (Reuters) - Britain's leading share index gained 0.6 percent in early trade on Thursday, snapping a three-session losing run following a late rally on Wall Street, with miners and banks providing the main strength.

By 0800 GMT, the FTSE 100 .FTSE index was 25.02 points higher at 4,163.77 after closing down 46.77 points, or 1.1 percent, on Wednesday at its lowest closing level in more than two months.

"Wall Street's late rally has given the market a bit of a boost, particularly the miners after Alcoa's results pleased, but, with news awaited from the Bank of England, overall interest is limited," said Mic Mills, senior trader at spread betters ETX Capital.

Overnight, the Dow Jones industrial average .DJI and the Nasdaq Composite .IXIC eked out gains as a late-stage rally brought stocks off their lows on hopes that the quarterly earnings season would deliver good news.