A self-confessed digital dinosaur, 63-year-old Hun Sen has recently taken to the web with gusto, posting daily Facebook updates and debuting a tailored app featuring news about his everyday life.
The strongman's Facebook page, minted in September, has already garnered 3.2 million 'likes', becoming one of the country's fastest-growing and most popular pages.
But his political rival, self-exiled opposition leader Sam Rainsy, has now accused the premier of hiring foreigners to create fake Facebook accounts to artificially boost his page's popularity.
The allegation came after the English daily Phnom Penh Post reported that nearly half of Hun Sen's thumbs of approval came from accounts based outside the country, mostly from India.
Rainsy's page has fewer overall 'likes' at nearly 2.3 million but more come from inside Cambodia, according to the report.
Hun Sen batted down the allegations Thursday while he was speaking at a university graduation ceremony in the capital Phnom Penh.
"I don't know where those 'likes' are from," he said, calling Rainsy a "loser who doesn't agree to lose".
"If I could buy India, I must be really strong. But I am just happy that I, Hun Sen, have been recognised by Indian people and people in other countries as the Prime Minister of Cambodia," he added.
Analysts say the premier's new but voluminous social media habits are an effort to woo young voters as he seeks to extend his more than 30-year grip on power ahead of local elections next year and a national poll in 2018.
"This is yet another sign Hun Sen is desperately trying to halt his waning popularity," Cambodian political analyst Ou Virak told AFP, adding that both Hun Sen and Rainsy have been spending money to advertise their pages.
Rainsy, who lives abroad to avoid arrest warrants he says are politically motivated, has long embraced social media to spread his message to young voters.
A 2013 election saw young Cambodians vote in droves for his Cambodia National Rescue Party (CNRP), wearied by the endemic corruption, rights abuses and political repression seen as the hallmarks of Hun Sen's rule.
The party says it was denied a majority in the election by vote rigging - AFP