PARIS, Jan 25 (Reuters) - French media conglomerate Vivendi has raised its stake in Spanish rival Prisa to 9.9% from 7.6%, Vivendi said on Monday. “Buying shares in PRISA is part of Vivendi’s ongoing strategy to become a global leader in content, media and communications, while extending its access to the Spanish-speaking markets in Europe, Latin America and U.S. Hispanics,” Vivendi added in a statement. Beleaguered Prisa, which is struggling with a huge debt pile, is controlled by activist fund Amber Capital which is led by French investor Joseph Oughourlian.