The Philippine Senate president says the impeachment trial of Vice President Sara Duterte will begin after Congress reopens in June and will be done fairly to avoid a repeat of a 2001 impeachment proceeding that stalled and sparked massive protests that forced a president to step down.

The Philippine lower house on Wednesday impeached Vice President Sara Duterte, the daughter of the country's firebrand former leader, setting the stage for a rare, high-profile trial in the Senate.

Members of the prosecution panel in the impeachment of Vice President Sara Duterte denied Thursday that ayuda or cash incentives were given to lawmakers to endorse the complaint, saying they did it based on merits.