Metro Manila (CNN Philippines) — National Irrigation Administration (NIA) Chief Peter Tiu Laviña has resigned from his post amid corruption allegations.

Laviña on his Facebook page on Tuesday said he wanted to quietly leave his post but he had to address the intrigues.

"Recently, there had been efforts to discredit me again. There are rumors circulating that I have asked money from NIA contractors. These are not true!" he said in a separate post.

Laviña said he decided to resign to spare President Rodrigo Duterte's administration from unnecessary intrigues.

"I have neither personal vested interest in it nor ill intent towards NIA and the whole government, which we are trying to reform," he said.

He said he will continue to serve the Filipinos even if he is no longer working for the government.

"This is your water boy, signing off!" he said, bidding his post good bye.

His resignation was also confirmed by NIA, saying Laviña rendered his irrevocable resignation this week effective Monday.

"As protocol, the second highest position will assume his post," NIA Public Affairs and Information Staff Filipina P. Bermudez said.

Laviña, the former campaign spokesperson of Duterte, was appointed as NIA Chief in November.

Duterte, in his speech last Friday, hinted he fired a Davaeño official for alleged links to corruption.

"As a matter of fact, I fired last night one taga-Davao na… for simply making a remark about... Sabi ko he's out and I told him even a whiff of corruption, talagang tatanggalin kita," Duterte said.

[Translation: As a matter of fact, I fired last night, one person from Davao for simply making a remark about... I said he's out and I told him I will remove you if you have links to being corrupt.]

The President has been vocal of his strong stance against graft and corruption under his government.

Laviña is the second Cabinet member to resign, first being former Housing and Urban Development Coordinating Council (HUDCC) Chairman Vice President Leni Robredo.

She resigned from HUDCC last December after she was asked by the President's Special Assistant Bong Go to desist from attending all Cabinet meetings.

CNN Philippines Senior Correspondent David Santos contributed to this report.