Pro-democracy activists in Burma say a constitutional referendum will be a "major battlefield" between the Burma's military leaders and those who want to get rid of the military dictatorship.
In a statement released Monday, the 88 Generation of Students, named after a brutally-suppressed 1988 uprising, called on the Burmese people to reject the charter.
The group accused Burma's military-led government of planning to unleash a wave of violence to intimidate the population into approving the charter.
On Saturday, the government announced plans to hold a referendum on a new constitution in May, and elections in 2010.
Burma's neighbors are welcoming its plans to hold a referendum and general elections. Singapore called the plans a "positive development" and expressed its hope that the referendum and elections promote national reconciliation.
Human rights groups warned it could be a tactic to ease international pressure for reform after the regime violently suppressed pro-democracy demonstrations last year.
The opposition National League for Democracy (NLD) said the announcement seemed erratic and vague. A spokesman, Nyan Win, said it does not make sense to set a date for an election before knowing the results of the referendum.
The government has not said whether the opposition will be allowed to take part in the elections.
The proposed constitution is believed likely to disqualify detained opposition leader Aung San Suu Kyi, because her late husband was a foreigner.
Burma last held elections in 1990, but the military has never recognized the victory of the opposition party. In 2003, the military announced a so-called "road map to democracy" that included drafting a new constitution.
A military government has ruled Burma since 1962. The current leaders are widely criticized for human rights violations and the detention of political activists.
Some information for this report was provided by AFP.