FTSE weaker led by banks on global economic woes

* FTSE down 0.6 percent

* Banks weak on global economic woes

* Sainsbury knocked by Deutsche Bank downgrade

* Selected miners rally on slightly easier dollar

By Jon Hopkins

LONDON, Sept 5 (Reuters) - Britain's leading share index fell 0.6 percent in opening trade, led lower by further weakness in banks on global economic woes and ahead of Friday's U.S. jobs report.

At 0808 GMT, the FTSE 100 index .FTSE was 35.0 points lower at 5,327.1, falling less sharply than in Thursday's 137.6 point slide.

"The modest opening decline is a bit of a surprise," said Ben Timms, senior trader at Blue Index, "Miners have popped it back a little bit after being sold off aggressively recently helped by a slightly easier dollar."