(Adds details and background)
By Jose Elías Rodríguez
MADRID, Feb 5 (Reuters) - Mexican billionaire Carlos Slim paved the way for a takeover of Spanish builder and services company FCC on Friday by agreeing with fellow major shareholder Esther Koplowitz to remove a limit on their holdings.
The two shareholders said they had signed an agreement allowing them to take their stakes beyond 29.9 percent as long as a planned capital increase took place before April 30.
A source told Reuters on Thursday that Slim was set to launch a full takeover bid for FCC after the rights issue and the only hurdle in the way was a shareholders' pact restricting the size of their stakes.
Slim's holding company Inversora Carso, is currently FCC's main shareholder with a 27.43 percent stake, closely followed by Esther Koplowitz, whose father founded the firm 70 years ago, with 22.44 percent.
But the 710 million euros ($795 million) cash call announced in December, which Slim has committed to buy into and guarantee, will likely push his stake above the 30 percent threshold that would require him to launch a full bid under Spanish rules.
Slim and Koplowitz had signed a shareholders pact after the Mexican bought into a previous rights issue at the end of 2014 forbidding either to hold more than 29.99 percent of the capital for at least four years.
Slim bought his initial stake at an average price of 9.75 euros per share and would now likely offer around 7 euros in a potential offer for the whole company, the price at which he recently bought shares.
FCC shares rose around 5 percent to 7 euros.
It is unlikely that Slim will gain full ownership, however, because most other shareholders are expected to buy into the rights issue - priced at 6 euros - while a bid at 7 euros may attract interest only from those who bought below that level.
But Slim's influence would rise in such a way that he would de facto fully control the company, which has been struggling with high debts and sluggish business since a property bubble burst in Spain in 2007. (Writing by Sonya Dowsett; Editing by Alexander Smith)