Reports from Costa Rica say Vice President and Justice Minister Laura Chinchilla is expected to resign in the coming weeks to seek the presidency in 2010 as a candidate of the National Liberation Party, or PLN.
It is not clear, however, when Chinchilla will announce her resignation.
The reports say Transportation Minister Viviana Martin is a possible candidate to replace the 49-year-old Chinchilla, who has previously served as public security minister.
Others who are expected to seek the presidential nomination of the PLN include former Security Minister Fernando Berrocal and a mayor, Johnny Araya.
Costa Rica's current president is Nobel Peace laureate Oscar Arias, who took office in 2006 for a second time. He first served as president from 1986 to 1990.
President Arias is also a member of the PLN, but under Costa Rican law, he is not eligible to run for the presidency again in 2010.