UPDATE 1-Spain's FCC CEO to leave company after summer - source
* CEO Juan Bejar to leave post before year-end
* FCC needs fresh strategy to shave debt and grow
* May make new rights issue to cut debt costs (Adds financial details, quotes, shares)
By Carlos Ruano and Robert Hetz
MADRID, July 10 (Reuters) - Spanish builder FCC's CEO Juan Bejar has told the firm he plans to leave before the end of the year, a source familiar with the matter said, a move that would see top shareholder Mexican tycoon Carlos Slim tightening his grip on the company.
The departure of Bejar, a well-known executive in the industry who was appointed in 2013, could take place after summer and would pave the way for another potential rights issue as well as a strategy change, the source also said.
FCC declined to comment.
The construction and services firm is struggling to boost profitability and cut a costly debt pile, even after Slim took a 25 percent stake when he bought the lion's share of a 1 billion euro ($1.1 billion) rights issue in December last year.
FCC is one of the worst performers on Spain's blue chip index and has lost a quarter of its stock value since the December rights issue, with uncertainty over Bejar's intentions since the arrival of Slim hanging over its shares. Continuación...