Britain's FTSE stalls after touching 15-year peak

* FTSE 100 flat after posting a new high

* New (KOSDAQ: 160550.KQ - news) index peak just 0.4 pct off December 1999 record

* Greek deal hopes underpin financials

* Coca-Cola HBC falls away on Russia tensions (Adds quotes, details)

By Alistair Smout

LONDON, Feb 18 (Reuters) - Britain's top share index edged up to a 15-year high on Wednesday, buoyed by optimism that a deal over Greek debt is in reach, although a crumbling ceasefire in Ukraine made investors cautious.

The FTSE 100 index touched 6,921.32, its highest since January 2000. That peak is only 0.4 percent off the record high of 6,950.60 set in December 1999.

Technical analysts said that while the new peak could spur the market on towards all-time highs, a failure to close above 6,900 could see the market drop away again.

"This could turn out to be a false breakout for, after all, it is not the first time the FTSE has peaked above 6,900 only to then stage a sell-off," said Fawad Razaqzada, technical analyst at Gain Capital (NYSE: GCAP - news) .

"A decisive close above 6,900 would be a particularly bullish outcome while below this key level would be bearish."

By 1120 GMT it was up just 0.15 points at 6,898.28, with traders citing mounting concerns over the situation in Ukraine.

Government forces started pulling out of a town in eastern Ukraine on Wednesday after a fierce assault by Russian-backed separatists which Europe said violated a ceasefire agreement.

"We see market risk led by Ukraine and geopolitics as among the key drivers for a move lower (in the FTSE)," Atif Latif, director of trading at Guardian Stockbrokers, said.

Strength in financials added more than 10 points to the FTSE, and hopes that Greece will secure a debt deal supported the market. However, the British blue-chip index underperformed the euro zone's Euro STOXX 50, up 0.7 percent after Greece said it intends to ask on Wednesday for an extension of its loan agreement with the euro zone.

Coca-Cola Hellenic dropped 3.6 percent, the top FTSE 100 faller, after the company reported a 11.4 percent drop in profits and on concern about developments in Ukraine. Its profits were hindered by its substantial exposure to Russia, which has seen sanctions imposed by the West over the conflict in Ukraine.

Among gainers, Intercontinental Hotels (Other OTC: ICHGF - news) rose 2.2 percent to lead the market, rebounding from a fall after its annual results on Tuesday.

Analysts said the share price was stretched after the hotel group reported results in line with forecasts, but the shares were buoyed on Wednesday by upgrades to its target price from UBS (LSE: 0QNR.L - news) and Jefferies. (Editing by Susan Fenton)