President-elect Rodrigo Duterte Jonathan Cellona, ABS-CBN News

DAVAO CITY - President-elect Rodrigo Duterte has told congressional leaders that he wants the shift to a federal form of government to go through a constitutional convention (con-con) composed of elected delegates, one of the lawmakers who met with him said Wednesday.

Duterte rejected a constituent assembly, which will be composed of incumbent lawmakers, saying he did not want to create the impression that he was "dictating" on Congress, Quezon Rep. Danilo Suarez told ABS-CBN News.

The 71-year-old, who will assume office on June 30, is poised to secure a "super majority" of more than 200 incoming members of the House of Representatives that will enable him to pursue his agenda, which also includes the reimposition of the death penalty.

"It's better to do it through con-con (constitutional convention) so there would be a clear exchange of views and we can explore the minds of the constitutionalists," Suarez quoted Duterte as saying during the meeting in the coastal village of Panacan on Tuesday.

READ: What is federalism? Lawmaker explains

Suarez, who is positioning himself as the leader of a "constructive minority," said Duterte told congressmen that he wanted a constitutional convention formed "as soon as possible."

Duterte is eyeing a federal government by 2020, his fourth year in office, Suarez said.

"He said that without federalism, you cannot contain the problems in Mindanao, and that's the only solution," the congressman said.

The Moro insurgency has killed tens of thousands of people and displaced millions in more than four decades of conflict in the southern Philippine island.

READ: Duterte expects long road towards peace, federalism