A Myanmar news journal editor on Monday won the World Association of Newspapers and News Publishers' annual media freedom award for years spent defying restrictions under the junta.

Than Htut Aung, head of Myanmar's Eleven Media Group, was presented with the Golden Pen of Freedom at the World Newspaper Congress in Bangkok.

"Building his newspapers from the ground up, he faced heavy government pressure and the ever-present censor's pen. Nonetheless, he consistently defied restrictions on freedom of expression," said Erik Bjerager, president of the World Editors Forum, who presented the award.

In 2010, one of Eleven Media's journals was banned for two weeks because of a message hidden in a headline following the release of Aung San Suu Kyi from house arrest that read: "Su free, unite and advance to grab the hope".

The end of decades of military rule in 2011 has ushered in dramatic reforms in Myanmar's media industry, including a relaxation of censorship and the release of imprisoned journalists.

Myanmar jumped 18 places to 151st out of 179 in media rights watchdog Reporters Without Borders' 2013 World Press Freedom Index.

Awarded each year, the Golden Pen recognises the efforts of an individual or group in the cause of press freedom.

Accepting his award, Than Htut Aung sounded a note of caution about the rapid changes, saying some people wanted to block the reform efforts in the country formerly known as Burma.

"I understand that after 50 years of dictatorship the road to democracy may not be a smooth one. We are still living under pressure and fear. We have to resist. We have to fight," he said.

The new freedoms have also thrown up new challenges for journalists in Myanmar, with Reporters Without Borders expressing concern at press coverage of deadly religious violence in the Buddhist-majority nation.

"The lack of reliable information about the violence, the poor and often biased media coverage and the reporting restrictions imposed by the government constitute new threats to freedom of information in Burma and pose a major challenge to the Burmese media," the group said in a January report.

Founded 13 years ago as a sports journal, Eleven Media now employs 450 people, including 140 reporters, and began publishing daily last month.