* FTSE 100 down 16.93 points at 6,681.08
* FTSE hits session high on talk of ECB deposit rate cut
* Ex-div stocks including Vodafone weigh on index
* BSkyB lifted by talk of BT deal
By David Brett
LONDON, Nov 20 (Reuters) - Britain's FTSE 100 was dragged down on Wednesday by heavyweight stocks such as Vodafone trading ex-dividend, but briefly pared its losses after a report that the European Central Bank was considering negative deposit rates.
Bloomberg reported that the ECB was considering a cut in its deposit rate to -0.1 percent from the current zero.
"Comments from the ECB about a potential minus 0.1 deposit rate if more easing is required is market-positive," said Atif Latif, director at Guardian Stockbrokers.
The FTSE 100 closed 16.93 points or 0.3 percent lower at 6,681.08, after spiking to a session high of 6,711 shortly after the report that the ECB was considering charging lenders for parking money at the central bank.
The main weight on the FTSE 100 was Vodafone, Britain's third-largest listed company by market capitalisation, which took 9 points off the index.
Carnival, Next, Sainsbury and Tate & Lyle traded ex-dividend on Wednesday as well.
ITV was among the worst-performing FTSE 100 stocks, falling 1.5 percent. Traders said the decline came after Bank of America Merrill Lynch downgraded the free-to-air broadcaster to "neutral" from "buy".
Ratings upgrades also set the course for some of the top gainers on the FTSE 100.
Fund firm Aberdeen Asset Management added 3.5 percent, topping the list of FTSE 100 risers, after BofA ML raised its recommendation on the company to "neutral" from "underperform".
EasyJet extended recent gains, climbing 2.4 percent, as HSBC upgraded the low-cost airline to "neutral" from "underweight" following results on Tuesday.
BSkyB rallied 1.2 percent after the pay-TV service said it wanted to make a deal with BT so each could offer its customers a full range of live sports. BSkyB slumped earlier this month after BT outbid it for exclusive rights to Champions League football.
The FTSE 100 remains up about 13 percent since the start of 2013 but has slipped from late-October highs of around 6,819.
It is now below a technical support line at the 23.6 pct Fibonacci retracement of the rally that started in October, at 6,701.16 points. The next support lies at the 38.2 pct Fibo at 6,627.73 and the 50-day moving average.
But traders remain bullish on the FTSE 100 for December, arguing that signs of an economic recovery in the UK would continue to support the stock market.
"Some portfolio adjustments are expected as the market seems to consolidate before a the next move. The market remains in an uptrend and momentum indicators suggest we could go higher," Guardian's Latif said.
JNF Capital trader Rick Jones said he thought the FTSE 100 was still on track to end 2013 around 6,900 to 7,000.