World Chess Championship a Kasparov match, either with 2002 FIDE champion Ponomariov, or 2004 FIDE champion Kasimdzhanov. Partly due to his frustration at the situation, Kasparov retired from chess in 2005, still ranked No. 1 in the world. Soon after, FIDE dropped the short knockout format for a World Championship and announced the FIDE World Chess Championship 2005, a double round robin tournament to be held in San Luis, Argentina between eight of the leading players in the world. However Kramnik insisted that his title be decided in a match, and declined to participate. The tournament was convincingly won by the Bulgarian Veselin
FIDE World Chess Championship 2005 be required to compete; but that as part of the "Prague Agreement", his defense of his title in the Classical World Chess Championship 2004 entitled him to direct entry to a match against the FIDE World Champion for the unified world title. After the tournament, he expressed his willingness to play such a match against Topalov. Although Topalov initially declined Kramnik's offer, he later acceded. The two contested the FIDE World Chess Championship 2006 to reunify the title, with Kramnik emerging the winner. FIDE World Chess Championship 2005 The FIDE World Chess Championship 2005 took place in Potrero de los