UPDATE 1-Belgacom cuts 2008 forecast after in line H1

(Adds details, background)

By Julien Ponthus

BRUSSELS, July 25 (Reuters) - Belgacom (BCOM.BR), Belgium's dominant telecom operator, cut its revenue forecast for 2008 on Friday after first-half results that were broadly in line with expectations amid price pressure on mobile calls.

The former state monopoly cut its 2008 sales forecast to a fall of about 2 percent from a previous prediction of a drop of up to 1 percent. It kept its EBITDA margin forecast unchanged at 33-34 percent.

Belgacom, the former monopoly operator, said first-half sales fell 2.5 percent to 2.96 billion euros ($4.64 billion) versus an average 2.95 billion forecast from a Reuters poll of six analysts.

Belgacom, whose mobile phone division Proximus is the market leader in Belgium, said earnings before interest, tax, depreciation and amortisation (EBITDA) came in at 1.02 billion euros, compared with the average of analysts' forecasts of 1.04 billion euros.

Belgacom also said its board of directors decided to approve a share buyback for a maximum amount of 200 million euros.

Belgacom's results come at a time when European telecom companies have posted mixed results.

While Vodafone's (VOD.L) decision to cut its revenue outlook on Tuesday sent shockwaves through the sector, Belgacom's main local mobile competitor Mobistar (MSTAR.BR) posted first-half figures above market expectations and raised its 2008 forecasts.