Hundreds of protesters opposed to a trade pact with China have invaded Taiwan's cabinet offices, marking a sharp escalation in a student-led movement against the island's rapidly developing ties with the communist mainland.

Up to 1,000 demonstrators gathered outside the building in Taiwan's capital Taipei throughout the day.

Taiwanese television stations showed scenes of protesters pushing and shoving police.

The protest comes five days after mainly student demonstrators occupied the nearby legislature after a ruling party politician reneged on a promise to submit the pact to legislative review.

Signed in June by representatives from Taipei and Beijing, the pact is awaiting ratification by Taiwan's legislature. It would open dozens of service sector industries in each side's territory to companies from either country.

Since the protests began, they have attracted tens of thousands of supporters to the area around the legislature. It is the sternest test so far for Taiwan president Ma Ying-jeou's six-year effort to bring the country's economy closer to China's.

Speaking earlier, Ma said going back on the pact would undermine Taiwan's economy and damage its international credibility.

Student leaders insist tying Taiwan too closely to China will harm Taiwan's hard-won democratic freedoms and pave the way for China's eventual takeover of the island. That has been the central goal of Beijing's Taiwan policy since the two sides split amid civil war in 1949.