Taiwan is voting in a presidential election in which both candidates favor closer economic ties with China.

Frank Hsieh, of the ruling Democratic Progressive Party, faces a tough battle against Ma Ying-jeou of the Kuomintang.

Ma, whose party has traditionally taken a more conciliatory line towards Beijing, has led consistently in opinion polls.

But analysts believe Hsieh may have narrowed the gap in the race to replace President Chen Shui-bian.

Hsieh has accused his rival of being soft on China and portrayed himself as the man best placed to defend Taiwan's interests.

Over 17 million people are eligible to vote and turnout is expected to be high. Polling stations opened at 0800 on Saturday (0000GMT), and close at 1600 (0800GMT), with results expected a few hours later.

'Resume dialogue'

The economy has been central to the election campaign.

Many Taiwanese think closer links with Beijing would help revive the island's faltering economy - but ties have been strained under President Chen because of his pro-independence stance.

Ma has proposed direct flights to the mainland and easing restrictions on doing business with China, calling for the creation of a "common market".

His rival has been more cautious, promising dialogue with China while pledging to defend Taiwan's sovereignty.

"In the past the DPP was criticized for not opening up but I will be more compromising, I will do better," Hsieh said as the campaign drew to a close.

Voting in the southern city of Kaohsiung on Saturday morning, he opened his arms wide and said: "I have this much confidence."

Television reports showed Ma Ying-jeou taking his usual morning run. He is expected to vote in Taipei in the afternoon.

'Second Tibet'

The recent unrest in Tibet has also become as key issue in the vote, with both men speaking out against Beijing.

Earlier this week Ma talked of a possible Olympic boycott if the situation there deteriorated, though he said on Friday he would not "push the issue to the extreme".

Hsieh warned that his rival could make Taiwan a "second Tibet".

China says that Taiwan is part of its territory, although the two have been separately governed since 1949.

It has threatened to use force if the island moves towards formal independence.

Also on Saturday, voters are also being asked to cast a ballot in two competing referenda on whether Taiwan should join the UN.

The more controversial version asks voters if the island should seek membership under the name Taiwan, rather than the island's official name, the Republic of China.

Many countries, including the US, have protested, saying the vote is unnecessarily provocative.

PHOTO CAPTION

Frank Hsieh, presidential candidate of Taiwan's ruling Democratic Progressive Party, emerges from a voting booth at a polling station, Saturday, March 22, 2008, in Kaohsiung, Taiwan.

BBC