Paraguay's President Horacio Cartes and Vice President Alicia Pucheta, attend a military parade marking the Independence Day celebrations. (Picture: Jorge Saenz/AP

Montevideo - Paraguayan President Horacio Cartes announced on Monday that he was resigning, less than three months before he was due to be succeeded by Mario Abdo Benitez, his conservative party companion who won the April 22 elections.

Cartes won a seat in the Senate in the same elections and needs to step down by mid-June to be sworn in as a senator on June 30.

"We have worked with great dedication for the development of our nation," Cartes said in a letter to the president of Congress, adding that he wanted to continue striving towards that goal.

Dario Filartiga, political advisor to Paraguay's President Horacio Cartes, talks to the media in Asuncion while holding Cartes' letter of resignation. Picture: Jorge Adorno/Reuters

However, Cartes' resignation needs to be approved by Congress. Some of the body's members have expressed concern that he wants to enter the Senate in order to gain immunity from prosecution.

Cartes has denied having links with drug traffickers.

If Congress accepts Cartes' resignation, he will be replaced by Vice President Alicia Pucheta until Abdo Benitez is sworn in August 15.