European shares led lower by telecom, bank stocks

* Markets retreat after Yellen-inspired gains on Wednesday

* Orange (LSE: 0OQV.L - news) , Bouygues (LSE: 0HAN.L - news) to extend talks - shares slip

* Italian bank stocks also fall

* TUI (LSE: 0NLA.L - news) , Carnival (LSE: CCL.L - news) rise after earning updates (ADVISORY- Reuters plans to replace intra-day European and UK stock market reports with a Live Markets blog on Eikon (see cpurl://apps.cp./cms/?pageId=livemarkets for site in development). Adds details, updates prices)

By Sudip Kar-Gupta

LONDON, March 31 (Reuters) - European shares fell on Thursday after solid gains made in the previous session following dovish comments from the head of the U.S (Other OTC: UBGXF - news) . Federal Reserve.

French telecom stocks and Italian banks underperformed.

The pan-European FTSEurofirst 300 index slid 0.9 percent. The index had risen 1.3 percent in the previous session after Federal Reserve Chair Janet Yellen's call for caution in raising U.S. interest rates buoyed global stock markets.

French telecom stocks were among the worst performers after Orange and Bouygues extended negotiations on a possible sale of Bouygues Telecom until Sunday, citing a lack of progress ahead of a Thursday deadline.

Orange shares fell 2 percent, while Bouygues declined 3.9 percent. Rival French telecom stocks also lost ground, with Iliad (LSE: 0MGY.L - news) dropping 2.4 percent, Numericable-SFR down 3.9 percent and Altice (Other OTC: ATSVF - news) fell by 1 percent.

"I was selling Bouygues yesterday. These bid talks often take longer than expected, and the longer they go on, there's always a chance it could unravel," said Rupert Baker, a European equity sales executive at Mirabaud Securities.

Shares (Berlin: DI6.BE - news) in Italian banks also slumped sharply, as three sources told Reuters that guarantor UniCredit (EUREX: DE000A163206.EX - news) was considering whether to delay Banca Popolare di Vicenza's 1.76 billion euro ($2 billion) rights issue, currently slated for April, if market conditions did not improve.

The fund-raising is regarded as a crucial test of investor confidence in Italian banks, whose shares have sold off sharply this year because of concerns about 360 billion euros of bad loans clogging their balance sheets.

"Investors fear that the recapitalisation of Popolare di Vicenza may end up with a large portion of unsubscribed rights, forcing UniCredit to take up a great part of it," ICBPI analyst Luca Comi said in a note.

The FTSEurofirst has recovered from lows reached in February but is still down by around 8 percent since the start of 2016. Concerns about a slowdown in China, the world's second-biggest economy, have hit world stock markets and commodity prices.

Tour operator TUI rose 4.4 percent, helped by a rise in summer bookings after the company said it was on track to meet its annual target, while cruise operator Carnival was also higher after a better-than-expected earnings update.

Today's European research round-up

ADVISORY- Reuters plans to replace intra-day European and UK stock market reports with a Live Markets blog on Eikon (see cpurl://apps.cp./cms/?pageId=livemarkets for site in development). In a real-time, multimedia format from 0600 London time through the 1630 closing bell, it will include the best of our market reporting, Stocks Buzz service, Eikon graphics, Reuters pictures, eye-catching research and market zeitgeist. Breaking news and dramatic market moves will continue to be alerted to all clients and we will continue to provide a short opening story and comprehensive closing reports.

If you have any thoughts, suggestions or feedback on this, please email mike.dolan@thomsonreuters.com.

Mike Dolan, Markets Editor EMEA.

($1 = 0.8801 euros) (Additional reporting by Danilo Masoni in Milan; Editing by Mark Heinrich)