GLOBAL MARKETS-World stocks fall on financial shares, oil drops

* European banking shares tumble after Goldman downgrade

* Oil eases nearly 1 pct as Iran responds to nuclear offer

* MSCI world index down 0.4 percent at 345.47

* Euro trades flat on less hawkish ECB (Adds European markets close, changes byline, changes dateline, previous LONDON)

By Elzio Barreto

SAO PAULO, July 4 (Reuters) - World stocks edged lower on Friday, getting no relief from a decline in crude prices as concerns of further banking write-downs weighed on financial shares.

Oil prices fell more than a dollar a barrel after Iran responded to an incentives package offered by six world powers in a bid to resolve a dispute over its nuclear development program.

But the decline in crude prices was not enough to give markets a boost, with European shares slumping after Goldman Sachs said banks may need to raise 60-90 billion euros in total. The broker lowered 2008-09 estimates for than 40 banks and said the sector would be hampered by the risk of additional capital raisings.

"It has become almost 'politically incorrect' to have banking stocks in a portfolio," said Alain Bokobza, head of strategy at Societe Generale in Paris.