The father of a man arrested for allegedly selling ecstasy in the Phillipines, and who may be facing the death penalty, said the family have vowed to support him “as much as we can”.

Damian John Berg was arrested alongside a Canadian man, Jeremy Eaton, in Makati City in Manila on Monday night, after allegedly being caught selling ecstasy by police.

“Damian is in custody and is being treated okay. It’ll take time for his case to be heard, and as family, we will be supporting him as much we can,” Geoff Berg told 9NEWS.

The Philippines Lifestyle reported the two men were arrested by Philippines National Police after the undercover officers bought 120 tablets of ecstasy from Mr Eaton, followed by another 50 tablets from Mr Berg.

Police allege the pair was connected to a drug ring in the Makati area, which was further linked to drugs sold at the Close-Up Forever Summer festival last month, where five people died from suspected drug overdoses.

Autopsies found heart failure, brain damage and organ collapse caused by ingesting a lethal amount of drugs had killed the group.

Both men have denied the allegations.

Mr Berg reportedly said he had “no purpose selling ecstasy” and had “a good paying job”.

Damian John Berg (left) was arrested in Makati City near Manila. (Facebook and Google Maps)

He told local media the drugs were someone else’s.

“I texted the individual and said why are you bringing this sh—here,” he told local station GMA.

The president-elect, Rodrigo Duterte, takes charge on June 30 and had previously condemned the drug-related deaths at the festival.

He favours capital punishment for crimes involving murder, rape or drugs.

“What I will do is urge Congress to restore the death penalty by hanging,” Mr Duterte said.

Both men will be charged with violations of the Comprehensive Dangerous Drugs Act.

Police allegedly recovered 255,000 pesos (AUD$7300) worth of street drugs and 100,000 pesos (AUD$2800) in marked money.

The Department of Foreign Affairs and Trade are aware of the matter.

"The department is providing consular assistance to an Australian man arrested in the Philippines," a spokesperson said.