The following article contains language that some readers may find offensive.

(CNN) Philippines President Rodrigo Duterte called the US ambassador to his country a "gay son of a bitch" in a speech, prompting US diplomats to raise the issue with their Filipino counterparts in Washington.

Recounting Secretary of State John Kerry's visit to the country, Duterte, speaking Tagalog, said that he was feuding with US Ambassador Philip Goldberg.

"I was with (incoming defense chief General) Delfin Lorenzana. We talked to Kerry, he was actually OK because I had a fight with his ambassador. I told him: 'your ambassador is a gay son of a bitch.'"

"I was annoyed at him, for interfering in the elections, giving statements here and there. He wasn't supposed to do that."

He also called Kerry "crazy" and suggested that he "offend" him more to get more aid.

JUST WATCHED Philippine President accuses officials of drug ties Replay More Videos ... MUST WATCH Philippine President accuses officials of drug ties 02:29

"Kerry came here, we had a meal, and he left me and Delfin $33 million. I said, OK, maybe we should offend them more, so this crazy will just give more money, just to make peace. So, it's all about the money."

Duterte's comments came as he addressed troops at the country's Armed Forces Central Command Headquarters on August 5.

US State Department spokeswoman Elizabeth Trudeau said the department had summoned the Filipino chargé d'affaires to "clarify" Duterte's remarks.

"We have asked the Philippines chargé to come into the State Department to clarify those remarks," she said at a briefing.

Goldberg has been the US ambassador to the Philippines since November 2013.

Photos: Newly inaugurated Philippines president Rodrigo Duterte (center left) stands next to outgoing leader Benigno Aquino (center right), during the departure ceremony for Aquino on June 30, 2016. Hide Caption 1 of 7 Photos: Duterte (left), also known as 'The Punisher' from his term as mayor of Davao City , has promised a ruthless and controversial war on crime as the chief focus of his six-year term. Hide Caption 2 of 7 Photos: Philippines Vice President Leni Robredo also took the oath of office on Thursday, calling for unity across the country following what became a divisive election. Hide Caption 3 of 7 Photos: Large crowds turned out to show their support to Duterte in Manila on June 30. Duterte won the 2016 election with 39% of the vote. Hide Caption 4 of 7 Photos: In the lead up to the inauguration, Duterte came into conflict with both the Catholic Church and the independent press, who weren't allowed into the ceremony. Hide Caption 5 of 7 Photos: Despite remaining popular in the Philippines, analysts have speculated the new, unpredictable president could lead to cooler ties between the United States and the Philippines. Hide Caption 6 of 7 Photos: Outgoing Philippines president Benigno Aquino (center), who was elected in 2010 for a six year term, told CNN Philippines he hoped he had left the Filipino population feeling empowered Hide Caption 7 of 7

President known for straight talk

JUST WATCHED Death toll rising in Philippines' war on drugs Replay More Videos ... MUST WATCH Death toll rising in Philippines' war on drugs 02:36

It's the latest offensive remark from Duterte, a leader not known for his diplomacy.

He took office at the end of June, after campaigning on a platform of tough policies on drugs and crime. The former mayor of Davao, a restive city in the southern Philippines, has long had a reputation for straight-talking and using offensive language.

On the campaign trail, he found himself having to defend comments made in 1989 regarding the rape and murder of an Australian missionary in a prison in Davao when he was the mayor.

"I was angry she was raped, yes, that was one thing. But she was so beautiful, I think the mayor should have been first. What a waste," he said of the attack.

He repeatedly refused to apologize for the comments and told the ambassadors of the United States and Australia, two of the Philippines' closest allies, to " shut their mouth " after they criticized his "joke." He also disowned an apology that was issued on his behalf by his political party.

He also cursed the Pope for traffic problems caused by the pontiff's visit to the Philippines.

"We were affected by the traffic. It took us five hours. I asked why, they said it was closed. I asked who is coming. They answered, the Pope. I wanted to call him, "Pope, (swear words), go home. Do not visit us again," he said.

Photos: Philippines drug crackdown Police patrol a shanty community at night during curfew on June 8, 2016 in Manila. Hide Caption 1 of 9 Photos: Philippines drug crackdown Some 1,000 people whom authorities accused of being drug users and dealers take an oath before local authorities after turning themselves in in Tanauan, the Philippines, on July 18, 2016. Hide Caption 2 of 9 Photos: Philippines drug crackdown A man authorities accused of being a drug user is fingerprinted during the mass surrender of some 1,000 alleged drug users and pushers in the Philippine town of Tanauan, located about 37 miles (60 kilometers) south of Manila on July 18, 2016. Hide Caption 3 of 9 Photos: Philippines drug crackdown A social worker gives counseling to those who have turned themselves in for drug-related crimes in the Philippines on July 18, 2016. Hide Caption 4 of 9 Photos: Philippines drug crackdown A woman cradles her husband, next to a placard which reads "I'm a pusher," who was shot dead in Manila on July 23, 2016. Hide Caption 5 of 9 Photos: Philippines drug crackdown A Philippine police forensic investigator displays packets of drugs and a hand gun found inside a shanty where members of a suspected drug syndicate were killed after a shootout with police on July 3, 2016. Hide Caption 6 of 9 Photos: Philippines drug crackdown A suspected female member of a drug syndicate is presented by police in Manila on June 22, 2016. Hide Caption 7 of 9 Photos: Philippines drug crackdown A gun, bullets, marked money and sachets of crystal meth are laid on a table after a drug raid in Manila on June 20, 2016. Hide Caption 8 of 9 Photos: Philippines drug crackdown Police officers stand in formation before the start of "Oplan Rody" on June 1, 2016, a law enforcement operation named after President Duterte, whose nickname is Rody. Hide Caption 9 of 9

The comments come as the President appears to have made a threat to reinstate martial law in the country, if the Supreme Court attempts to thwart his war on drugs.

Speaking to troops on the restive island of Mindanao Tuesday, he said: "If this (attempt to thwart the war on drugs) continues, you want to stop me, well then... if all goes awry, or would you rather that I declare martial law?"