The jailing of two Reuters journalists in Myanmar over their reporting of the Rohingya crisis is "deeply troubling", US Vice President Mike Pence said Wednesday, describing a "free and independent" media as a core American value.

Speaking to Myanmar's de facto leader Aung San Suu Kyi on the side-lines of a summit in Singapore, he criticised the seven-year sentence meted out to Wa Lone, 32, and Kyaw Soe Oo, 28, over their coverage of a massacre of Rohingya men during an army operation last year.

The pair, both Myanmar nationals, were charged under the draconian state secrets act after meeting police who handed them documents.

Reuters have appealed the verdict insisting they were entrapped by authorities to muzzle reporting of abuses by Myanmar's powerful military.

Pence said America placed a "premium" on "a free and independent" press and said he would take the matter up with Suu Kyi in their private talks.

The verdict against the Reuters reporters sparked widespread condemnation as a brazen effort to intimidate Myanmar's nascent community of journalists.

"In America we believe in the freedom of the press," Pence added.

Pence's boss President Donald Trump has a notoriously combative relationship with the media, routinely describing journalists as "enemy of the people" and dismissing critical reporting as "fake news".

© AFP