* Forecasts Q1 organic sales growth of around 6 pct
* 2010 operating margin 23.6 pct, in line with forecast
* Shares down, outlook, dividend disappoint
* JCDecaux "natural buyer" of CBS Outdoor assets - co-CEO
(Adds co-CEOs comments on CBS Outdoor, updates shares)
By Dominique Vidalon
PARIS, March 9 French outdoor advertising company JCDecaux (JCDX.PA) will not pay a dividend on last year's profit in order to leave it scope for acquisitions that could include the billboard business of CBS Corp (CBS.N).
The world's largest outdoor ad group by revenue, which said late last year it could pay a dividend for the first time in three years, also forecast organic first-quarter sales growth of around 6 percent after 2010 earnings met forecasts.
Growth reached 9.1 percent last year as ad spending recovered, the group said on Wednesday.
"We can confirm that the positive momentum mentioned in January has continued," co-Chief Executive Jean-Charles Decaux said.
Jean-Charles and brother and co-CEO Jean-Francois Decaux told a news conference they would be interested if CBS's outdoor ad unit was put up for sale.
"If the dossier came up, we would look at it," Jean-Charles Decaux said.
"We looked at it in the past. We could not afford it ... Today, this asset is less expensive," Jean-Francois Decaux said, adding that recent comments from CBS officials suggested an increased likelihood that CBS would exit billboards.
JCDecaux wants to increase its market share in the United States and is a "natural buyer" for the assets, along with U.S. ad group Lamar (LAMR.O), Jean-Francois Decaux added.
JCDecaux, which competes with Clear Channel Outdoor (CCO.N), specialises in billboards and signs contracts with cities and transport authorities to put ads on bus stops, in metro stations, airports and other public spaces.
The group, 70 percent owned by the family that founded it in the 1960s, did not pay a dividend for 2008 or 2009.
JCDecaux said on Wednesday it wanted to "maximise financial flexibility ... (and) ... ensure that we are well prepared to seize consolidation opportunities, should they arise".
JCDecaux shares were down 1.22 percent at 1247 GMT, underperforming a 0.47 percent higher European media sector .SXMP.
Exane analyst Charles Bedouelle said investors had expected JCDecaux would pay a 2010 dividend of 2 euros per share.
The sales outlook "may be mildly appreciated by the market, which anticipates 7-8 percent growth for full-year 2011, with Q1 showing the easiest comparable base", he said.
French advertising group Havas EURC.PA reported January-February organic growth of 7.7 percent on Tuesday. [ID:nLDE7272AO]
JCDecaux's operating profit rose 42 percent to 555 million euros ($771 million) last year, helped by cost cuts. The operating margin rose 3.2 percentage points to 23.6 percent, meeting forecasts and reflecting better margins in the group's three divisions -- street furniture, transport and billboards.
Free cash flow doubled to 327 million euros.
"The (results) publication is, overall, in line with expectations, with stronger-than-expected cash generation," CM-CIC analyst Eric Ravary said.
The group forecast a 14-16 percent margin at its transport unit this year and 15-20 percent for billboards, with capital expenditure of 175-180 million euros.
JCDecaux shares have gained 2.6 percent this year, underperforming a European media index .SXMP up 3.6 percent. ($1=.7201 Euro) (Additional reporting by Gwenaelle Barzic; Editing by Dan Lalor and Will Waterman)