TAIPEI (AFP) - Student protesters occupying Taiwan's legislature to stop the government from ratifying a contentious trade pact with China on Friday called on the public to surround the ruling party's offices after their ultimatum was ignored.

The protesters say the deal will damage Taiwan's economy and leave it vulnerable to political pressure from China, allegations rejected by the Kuomintang party.

"We call on the public to surround tomorrow the offices of the Kuomintang around the country and step up pressure on Kuomintang legislators," student leader Lin Fei-fan said from the main chamber of parliament which the group occupied on Tuesday night.

Lin also asked more people to attend a huge rally outside parliament, which rapidly swelled to 12,000 from just a few hundred at the beginning of the protest.

The announcement, broadcast live on television, came after the protesters' ultimatum expired at noon.

In a statement, President Ma Ying-jeou called for a peaceful end to the standoff, saying a consensus should be reached in "rational and democratic ways".

"President Ma hopes the parliament will resume functioning soon to ensure the constitutional order so the dispute can come to a peaceful end," it said.

Police have set up barbed-wired barricades outside the presidential office while some 2,000 officers have been deployed in and around parliament, as the 200-plus protesters were mulling their counter-measures.

The protesters - mainly young students - stormed security barriers and took over parliament's main chamber late Tuesday in the first such occupation of the building in Taiwan's history.

Hundreds of police attempted to barge their way in on Wednesday and end the occupation, but they failed to breach the improvised barricades fashioned by the students out of piles of armchairs.

Protesters have demanded Ma "return" the service trade pact to China, rejecting the government's bid to push ahead with plans to ratify it despite opposition from the public.

Emotions were also high among the crowd who rallied outside parliament in support of the protesters in what some local media have termed Taiwan's "Jasmine Revolution".

Some demonstrators waved placards calling Ma a "dictator" while others applauded and cheered after painting huge protest slogans reading "When dictatorship becomes real, revolution should be obligation" on the top and front wall of the parliament building.

"While the students remain inside we will be outside to support them. They are doing this for democracy and for Taiwan," said Su Tseng-chang, chairman of the leading opposition Democratic Progressive Party.

Signed in July, the agreement is designed further to open up trade in services between China and Taiwan, which split 65 years ago after a civil war.

The Kuomintang government has said the agreement is a litmus test of Taiwan's resolve to open its markets, warning that failure to ratify the agreement would be a grave setback in efforts to seek more free trade agreements by the trade-reliant island.

But the protesters said they had something to fear, citing Hong Kong's experience since the former British colony returned to China in 1997, with concerns about press freedom and tensions over a massive influx of Chinese tourists.

"I've growing complaints about the Ma government in my mind. I decided to stand up this time, because I fear the agreement might have grave and negative impacts on my future," Lin Chia-yi, a student from National Chengchi University, told AFP.

"My friends from Hong Kong ask me if people here would like to see Taiwan become another Hong Kong." The pact passed its first parliamentary hurdle on Monday after it was approved by a committee, but the opposition insisted the approval was illegal.

The pact is a follow-up agreement to a sweeping Economic Cooperation Framework Agreement signed in 2010 to reduce trade barriers between China and Taiwan.

Ma has overseen a marked thaw in relations with Beijing since he came to power in 2008, pledging to strengthen trade and tourism links.

But China still considers Taiwan as part of its territory awaiting reunification - by force if necessary.