Taiwanese protesters who have occupied parliament for three weeks to try to block a contentious services trade agreement with China said Monday they would end their protest this week after claiming success.

The demonstrators -- mostly young students -- occupied the main chamber on March 18 in the island's first-ever such protest.

"We'll walk out of parliament at 6:00 pm (1000 GMT) Thursday. We also invite all friends to come and meet us outside parliament," student leader Chen Wei-ting announced in a televised press conference.

Chen said the sit-in had stopped President Ma Ying-jeou from pushing through a "secret deal between the Kuomintang party and Chinese Communist Party".

But demonstrators vowed to push the Kuomintang administration to retract the services trade agreement, a demand which Ma has rejected.

"Ma has been dictatorial and refused to listen to people's opinions. What the protest has reflected was simply the tip of an iceberg," Chen said.

Politicians from the China-sceptic opposition Democratic Progressive Party accuse Ma of trading Taiwan off to China in exchange for marginal economic benefits.

"People have stood up. We want to tell them we're the master of the island. We've the right to decide on our own future," Chen said.

Around 200 student-led demonstrators occupied the chamber on March 18 and swiftly drew a large crowd of supporters, with more than 10,000 congregated outside at one point.

There were violent clashes on March 23 when baton-wielding police turned water cannon on protesters who had stormed the nearby government headquarters.

And on March 30 tens of thousands gathered to pressure the embattled Ma to retract the services trade pact, which they say will damage Taiwan's economy and leave it vulnerable to political pressure from China.

The decision to call off the sit-in came after parliamentary Speaker Wang Jin-pyng of the ruling Kuomintang entered the main chamber Sunday to meet the protesters.

- Speaker's 'goodwill' gesture -

He pledged not to preside over further parliamentary debate about the services trade pact until a law has been introduced to monitor such agreements with China.

Protesters described his promise -- made without reference to Ma -- as a "goodwill" gesture.

Politicians from both ruling and opposition parties have been meeting the students since the occupation, but Sunday was the first time that the speaker had entered the chamber since it was seized.

Ma, who has pursued closer ties with China since taking power in 2008, has agreed to the students' demand for a law to monitor all pacts with China, but the protesters have rejected the government's bill.

The latest pact would further open up trade in services between China and Taiwan, which split 65 years ago after a civil war.

Ma has said failure to ratify it would be a grave setback to efforts by trade-reliant Taiwan to seek more free trade agreements and avoid isolation as regional economic blocs emerge.

The deal 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 pledging to strengthen trade and tourism links.

He was re-elected in January 2012 but his approval ratings are currently only around 10 percent.

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