A Malaysian minister has quit his post in protest about the government's crackdown on the opposition by using a draconian law which allows indefinite detention without trial. As VOA's Nancy-Amelia Collins reports from Jakarta, the government is facing mounting pressure from the opposition, which vows to topple the government this month.

Malaysian Law Minister Zaid Ibrahim sent his letter of resignation to Prime Minister Abdullah Ahmad Badawi, Monday, saying he was resigning because of the government's use of the Internal Security Act, which allows for indefinite detention without trial.

In the past few days, the government used the ISA to arrest an opposition member of parliament and two journalists. One of the journalists has been released, but the other two people are still being held.

Political analyst Koo Kay Peng says the resignation puts the government under intense political pressure and doubts the ruling coalition will continue the crackdown against the opposition.

"I think initially we see that there is a potential [for a] second wave of crack-down," he said. "But from the way we look at it now, it will be very difficult because one thing for sure is that the decision to use the ISA is not supported by the coalition partners. And, as of today, law minister Zaid Ibrahim has just quit over the decision of the government using ISA. So, I think it will be very difficult for further crackdown."

Opposition leader Anwar Ibrahim - a former deputy prime minister - will lead an opposition rally Monday evening and says he is still confident of toppling the government.

In the March general elections, the opposition won a third of parliament, but the ruling coalition still has the power.

Anwar says he needs just 30 lawmakers to switch sides, to seize power.

Opposition leader Anwar earlier vowed to topple the government by September 16, but admits it may take longer, especially since the government sent 50 lawmakers on a trip to Taiwan, last week.

But political analyst Koo says the exact date is not important, what is important is the fact the winds of change are blowing through Malaysia.

"We should not be fixated over the 16th of September deadline," he said. "That is a very symbolic date and Anwar used that symbolically to show that his fight is to unite Malaysians and we need to promote a new Malaysia. And, the formation of Malaysia happened 45 years ago on that exact date. But I believe that Malaysians are now a lot more mature lot. We should focus on the movement for change. And, this movement for change does not look stoppable."

Prime Minister Abdullah faces further challenges on September 18, when his United Malays National Organization will meet, amid calls from within the party for his resignation earlier than the 2010 agreement.