TAIPEI - Taiwan will reduce the size of its armed forces by a fifth as ties improve with long-time rival China, a defence ministry official said Wednesday.

The defence ministry hopes to cut the number of troops from 275,000 at present to 215,000 within five years, the official said, adding that around a quarter of the generals would also be phased out.

But the official, who requested anonymity, cast doubts over whether the ministry could meet its plan of scrapping compulsory military service by 2014.

"In a word, money is the major problem," he said.

Currently, all men aged 20 are required to spend a year in the armed forces.

A group of top military officers, during a backgrounder briefing with reporters Tuesday, renewed the ministry's plan of replacing conscripts with professional soldiers.

Proponents argue that the conscription policy needs to be overhauled as the armed forces have struggled to enhance their defence capabilities as conscripts are unable to become proficient with high-tech weaponry during their short military service.

However, the new proposals sparked concerns over whether the defence ministry would be able to recruit professional soldiers at a monthly salary of 35,000 Taiwan dollars (1,000 US).

The plan to phase out conscription was a campaign pledge of President Ma Ying-jeou during the 2008 election.

Taiwan's relatively large army is a legacy of decades of tensions with China, which has regarded the island as part of its territory awaiting reunification since the two sides split at the end of a civil war in 1949.

However, ties have improved dramatically since Ma of the China-friendly Kuomintang party came to power last year promising to boost cross-Strait trade and tourism.