During a public speech just over a week ago and in decidedly unpresidential language, Mr Roh said he opposed the amount of time Korean men were forced to spend 'rotting in barracks', and raised the possibility of reducing the time spent in national service.

The comments by the country's commander-in-chief provoked an angry response from past armed forces heads and former defence ministers, who accused the president of disparaging the military.

'We are strongly opposing an attempt to cut the military service period for political objectives,' said a statement by 70 former top brass.

They believe Mr Roh is raising the possibility of a cut in conscription as a populist move ahead of elections next year, an interpretation shared by political analysts.

'President Roh may be hoping to pave the way for a person to be elected who will follow in his footsteps with his policies and political line,' said Chung Hee, political science professor at Hankuk University of Foreign Studies.

By law, all fit young Korean men must do around two years of military service. Advocating a cut in conscription is likely to prove popular with young voters, who regard the duty as onerous and disruptive to careers and education.

'It was a complete waste of time, at a time in my life when I could have been doing more important things,' said Ha Tae-wook, now in his 30s.

But many older South Koreans still regard military service as an important rite of passage for the country's young men that can instil a sense of discipline and group solidarity.

'It's an obligation to defend the country. We must understand the reality, we have an aggressive North Korea on our doorstep,' said a father of two boys, one who is serving and a second who has completed national service.

Analysts say this latest clash with another of the country's entrenched interest groups is an attempt by the president to retain a role in domestic politics amid calls for him to occupy himself with the administration of the country and detach himself from the rough and tumble of daily politics.

Under the country's one-term presidential system, Korean presidents are normally relegated to political oblivion towards the end of their administration. By highlighting the subject, Mr Roh has raised the prospect of conscription becoming a significant issue in the presidential campaign.

During the four years of his presidency, Mr Roh, who is viewed as an outsider, has thrived on upsetting establishment groups, whether in the media, military or business.

This episode is the latest salvo in a long-running tense relationship that pits the conservative military against the liberal political leader.

Military leaders have long opposed what they see as the administration's pursuit of unconditional support for improved inter-Korean ties and Mr Roh's drive to inject greater independence into South Korea's relationship with the US, reflecting a deep, fundamental ideological split between the military and the political leadership.

'The whole belief system of military groups - that we are unsafe because of the threat from the North, that we need a close alliance with the US - these things cannot be changed within the space of a four- or five-year presidency,' said Professor Lee.