Mr Ma, of the Kuomintang, swept to a landslide victory in March largely on pledges to improve the island's sluggish economy, vowing to achieve six per cent annual economic growth, although he gave no timeframe.

Mr Liu went further and said that he would step down if he fails in four years to achieve targets of six percent economic growth and keeping inflation below three percent.

However, Mr Ma admitted for the first time in an interview with a foreign newspaper on Wednesday that 'the (Liu's) timeframe of the economic targets may have to be deferred' given the global economic downturn.

'If I can be re-elected for another four-year term, we hope the targets could be reached in 2016, or the last year of my office.'

Last month, the government lowered its GDP growth forecast for 2008 to 4.30 per cent from 4.78 per cent forecast in May, saying consumption has been hurt by rising inflation.

Mr Ma's comments and apparent backtrack irked the opposition Democratic Progressive Party (DPP).

'People voted for Ma in order for a better living. Now the hope is dashed.

'With the economic sluggishness and the government doing little about it, Ma should apologise to the people for failing to deliver the promises he had made during the election campaign,' DPP spokesman Chen Wen-tsan said.

Angry DPP legislator Tsai Huang-lang demanded Liu 'to step down immediately'.

Tens of thousands of people took to the streets of Taipei last week to protest what they said was Ma's China-friendly policies and his failure to lift Taiwan's economy. -- AFP