MANILA - Presumptive president Rodrigo Duterte has picked former justice undersecretary Jose Calida, a former official during the Arroyo administration, as Solicitor General for the incoming administration.

Calida, who served as one of Duterte's campaign managers, will replace incumbent Solicitor General Florin Hilbay.

Speaking to ANC, Calida said he was surprised about his appointment, saying he was outside his office when he received the news.

"In his best judgment, he [Duterte] probably thought I will be the solicitor general that he prefers in his Cabinet," he said.

A former candidate for the position of Ombudsman in 2011 and a practicing lawyer since 1974, Calida said the work of a solicitor general is not easy "but we can handle it."

"Knowing our presumptive president, the marching order is to do your best and I will do it," he said.

Asked to react to claims that the incoming administration is "rehashing" the Arroyo administration, he said: "I am a lawyer and my loyalty is to the rule of law. It doesn't matter who is the one who appointed me. When I become the solicitor general, I will take an oath to defend the Constitution and enforce the rule of law regardless of who the appointing authority is."

Calida, in a 2015 speech, described Duterte as "a mayor who can make things happen."

"Pundits call it 'political will'. But in Davao, it's no big deal. It's just Mayor Duterte's usual way of doing things. Hindi siya palpak," Calida told a gathering of the Volunteers Against Crime and Corruption (VACC).

A Philippine Star report earlier said Calida was part of a "power struggle" in the Department of Justice after he was named acting secretary of justice, and not Undersecretary Merceditas Gutierrez, under then Secretary Simeon Datumanong.

Calida was also the subject of a "white paper", which questioned his act of reversing resolutions of the sitting secretary and assailed his large number of bodyguards.

Calida, however, said he needed bodyguards after the kidnapping of his wife.

He also said "some people in the department" who were envious of him were circulating the "white paper" to sully his reputation.