By Jack Kimball
BOGOTA (Reuters) - Colombian President Juan Manuel Santos said on Saturday he would not remove his embattled defense minister in a cabinet shake-up despite growing criticism over an increasing number of attacks by Marxist guerrillas in Latin America's No. 4 economy.
Two years into his four-year term, the 61-year-old Santos is reshuffling his 16-member cabinet to shore up slumping approval ratings and strengthen his support base within the ruling national coalition ahead of his likely re-election bid in 2014.
In his weekly televised address, Santos said he was confirming Defense Minister Juan Carlos Pinzon in his post as well as Foreign Minister Maria Angela Holguin.
Analysts had believed that Pinzon was on the list of ministerial changes since the perception that security was deteriorating had damaged Santos' once-commanding popularity.
Last week, Santos asked all his ministers to submit resignation letters to set the stage for a cabinet shuffle. In a surprise move, Finance Minister Juan Carlos Echeverry was replaced by Energy Minister Mauricio Cardenas. The transport minister is also expected to be replaced.
Santos must still name a new minister of mines and energy, who would be the third person to hold the post in two years.
Once an investment outcast as drug-running rebels kidnapped, killed and attacked rural areas, Colombia has seen a dramatic security shift, attracting billions of dollars in foreign investment over the last decade after a U.S.-backed crackdown.
After winning the presidency in a landslide in 2010 and riding on high approval ratings that let him push key economic and political reforms through Congress, Santos has faced increasing criticism, especially from ex-President Alvaro Uribe.
Leftist guerrillas have also stepped up the number of attacks, especially against oil installations, a worrying trend for one of the economy's fastest-growing sectors.
In an interview with Reuters last month, Santos rejected accusations that FARC rebels were making a comeback, describing recent assaults as a last-gasp effort to grab headlines that did not pose a threat to economic prosperity.
(Reporting by Jack Kimball; Editing by Sandra Maler)