Armenia's new prime minister said he would fight graft with any means possible, after being swept to power on the back of mass street protests, in one of his first conversations with foreign media, AFP says.

Nikol Pashinyan was elected by parliament last month after he spearheaded weeks of social media-fuelled demonstrations against veteran leader Serzh Sargsyan and his ruling party.

Pashinyan told AFP and other French media he would use the likes of Facebook and Twitter to cleanse the poor ex-Soviet nation of widespread corruption, one of its main scourges.

A judge who takes a bribe could be publicly named and shamed on the sites, he said.

"Really, a solution to some problems is much simpler" than one might think, he added.

The prime minister and his supporters accused Sargsyan of clinging to power and failure to root out mass poverty and corruption in the country of 2.9 million people, nestled at the crossroads of Europe and Asia.

Pashinyan has a large online following and the number of people visiting his Facebook page and Youtube channel exceeds the number of Armenians living in the country and outside its borders, the father of four said.

He plans to lead by example.

"It's not by spending thousands of dollars that one should fight corruption, it's simply about the number one not being corrupt, that's all," he said.