Taiwan: Anti-Secession Law
Some say it could even provide the legal justification for Beijing to invade the island.
Among those taking part was 56-year-old Wei Quo, who now lives in Alberta, Canada.
"I'm a Taiwanese and this country is facing a crisis," he said. "I have dual citizenship now, but I love this land.
"It's important for me to sign this petition - to send a message to our government and the world that we oppose any plans by China to annexe Taiwan."
He is not alone in his fears. Concerns have been mounting in Taiwan, ever since China first announced plans to introduce an anti-secession bill back in December.
The law is expected to be passed by China's parliament, the National People's Congress, in a session which opens on Saturday.
The text has still not been made public, but it is likely to reinforce China's claim to sovereignty over Taiwan and its willingness to use military means to block any moves towards independence.
Various public opinion polls on the island have shown that more than three-quarters of respondents are opposed to the draft law.
In recent weeks, scarcely a day has gone by without Taiwanese government officials voicing their fears over the bill.
Officials were even despatched overseas to lobby international support.
Suggestions that the European Union may soon lift its embargo on weapons sales to China - an embargo which has been in place since the 1989 Tiananmen Square massacre - has only added to the jitters.
Chinese officials have said in recent weeks that the bill would stress peaceful unification and the "one China, two systems" principles.
It is also likely to propose ways of encouraging more cross-straits
visits, they said.
But Taiwan's top official responsible for the island's policy towards China, Joseph Wu of the Mainland Affairs Council, said the anti-secession law would "wreck" cross-strait relations - which have showed tentative signs of improving following the recent resumption of the direct flights between Taipei and Beijing.
"It's provocative and a unilateral change of the status quo," he said of the draft law.
"China's vicious attack on Taiwan through this law is totally unhelpful and unnecessary. We urge them to re-think it."
Taiwan's President Chen Shui-bian has called the draft law a dark cloud overshadowing efforts by his government to improve ties with Beijing.
He warned that it posed a threat to regional security and stability, and increased pressure on his government to hold a referendum to counter the move or enact an "anti-annexation law".
That has already begun to happen. The island's pro-independence party, the Taiwan Solidarity Union (TSU) - an ally of the president's Democratic Progressive Party - is pushing for such a law.
But with just 12 seats in the 225-seat legislature, many believe its is unlikely to win enough support.
The TSU is also collecting thousands of signatures and holding
rallies opposing China's plans.
"Taiwan people are under the threat of China... first by its missiles, now by this anti-secession law, which threatens a legal war across the Taiwan Strait", said the TSU's director of policy, Shangren Lee.
"If the law is passed, it might limit Taiwan's space internationally," he said.
But Mr Lee also said the law could unite the island in opposition to China, and have the opposite of the intended effect, further isolating the people of Taiwan from the mainland.
The government - while vocally opposing the law - appears to be heeding calls by Washington to avoid any action that could make a peaceful resolution more difficult.
"We are trying to be reasonable, and to appeal to the international community," said National Defence Vice-Minister Tsai Ming-hsien.
"We are a humble people - but when we are forced, to some extent, we have to react.
"We have to make people aware that this law is a threat - a soft threat, not a military one - but still it's a threat to our survival," he said.
Many analysts believe China is sending out contradictory messages.
On the one hand Beijing has appeared flexible on the issue of charter flights to and from Taiwan, according to George Tsai at Taiwan's Institute of International Relations.
But then at the same time, he added: "They are doing everything they can do to prevent Taiwan from drifting further away and moving towards... independence. Politically they are trying to isolate Taiwan.
"In Chinese we say the soft hand becomes softer and the hard hand becomes harder."
Others believe the law may not prove as detrimental as many have feared.
Among them is Emile Sheng, Associate Professor of Political Science at Soochow University.
"No one has seen the draft. If it only states the absolute red line... it might not actually make things worse," she said.
"As long as both sides know where the red line is, we might even see a more stable situation if the law is passed."
Optimists suggest that China may be listening to critics of the proposed law - and this will be reflected in its final wording.
But until it is made public, no one will know for sure.
Source: BBC News