* FTSEurofirst 300 down 0.3 pct, Euro STOXX 50 off 0.4 pct
* Oil and energy shares are worst-performing sector
* Concerns remain over Spain and Greek debt problems
* Dividend yields still favour stocks over bonds for some
By Sudip Kar-Gupta
LONDON, Oct 4 (Reuters) - European shares fell on Thursday, led by weaker energy stocks, while persistent worries over the euro zone debt crisis also weighed on equity markets.
The FTSEurofirst 300 index fell 0.3 percent to 1,098.04 points, while the euro zone Euro STOXX 50 index declined by 0.4 percent to 2,482.04 points.
Concerns over Europe's sovereign debt problems, which will be in focus at the European Central Bank's rate-setting meeting on Thursday, have kept major European stock markets within a tight trading range over the past week.
Spain is under increasing pressure to accept a sovereign bailout package, while Greece is struggling to meet the terms of its earlier international rescue deal.
A Spanish bond sale attracted increased demand on Thursday on prospects Spain will soon seek European aid to cut its debt costs, but some investors have been reluctant to commit further to equities while the timing of any such aid request remains uncertain.
"I see the Spanish situation getting clearer but not necessarily any better," said JN Financial investment manager Edward Smyth.
Smyth added he had taken out "short" positions - which bet on future falls - on Britain's FTSE 100 index and Germany's DAX equity index ahead of the ECB meeting, which is expected to leave interest rates on hold.
The STOXX European oil and gas index was the worst-performing equity sector, falling 1.3 percent. Shares in British oil major BP declined after disruption to its Azeri gas flows to Turkey.
European stock markets are still up from year-low levels reached in June following steps taken by world central banks from July onwards to inject fresh liquidity in order to fight off the economic slowdown and Europe's debt problems.
The FTSEurofirst 300 is up around 8 percent since late July, when ECB head Mario Draghi promised "whatever it takes" to protect the euro currency, while the Euro STOXX 50 is up around 10 percent since that point.
Some investors expect Draghi to provide hints about Spain's likely move regarding an international bailout at the ECB's rate meeting.
Spain must first formally request aid before the ECB can activate the bond-buying programme, which is aimed at lowering the borrowing costs of debt-ridden states.
"There's just a little bit of optimism that there could be some more easing coming from the ECB," Berkeley Futures associate director Richard Griffiths said.
Griffiths said he would look to sell Euro STOXX futures contracts, which were down 0.4 percent, to lock in profits after gains on the contract in recent days.
Other traders added that central bank stimulus measures had pushed benchmark bond yields to such low levels that investors would still favour equities at present due to the better yields on offer via equity dividends.
"The demand for equities is still there. There's no value being in bonds at the moment. Any time we have a pullback, the buyers come back out of the woodwork," said McLaren Securities managing director Terry Torrison.