Paraguay's President Horacio Cartes has suffered at least a temporary a setback in his effort to take up a Senate seat once his term ends in August.

Opponents both outside his own party and within it boycotted a congressional session on Wednesday. The lack of a quorum blocked a vote on his resignation request.

He needs to leave office by June 30 to be sworn in with other senators because Paraguay's constitution says he can't hold two offices at once.

Cartes couldn't seek re-election and the Senate seat would be a way to extend his political influence. Some experts argue it also might help block any possible prosecution on corruption allegations.

Analysts say Cartes still has plenty of time before the deadline to win enough votes.