Thai Prime Minister Thaksin Shinawatra has again refused to resign, despite an intensifying political crisis.
Mr Thaksin wants supporters to write to him
Mr Thaksin vowed to hold his own pro-government rally on Friday, to counter a huge opposition demonstration planned for Sunday.
Rumours are even circulating of a military coup, but the head of the country's armed forces denied on Wednesday that this was a possibility.
Mr Thaksin is accused by his critics of corruption and abuse of power.
"I guarantee that I will not resign from my position," Mr Thaksin told reporters after meeting with leaders of his ruling Thai Rak Thai party.
"I will handle my responsibilities in this position as well as I can."
He called on his supporters to send him positive messages which he could post outside his government offices to discourage his opponents.
His critics are pressuring Mr Thaksin to step down before Sunday, or face the biggest show of opposition yet - a rally the organisers vow will attract tens of thousands of people.
Supreme Commander General Rueangrot Mahasaranon, head of the Thai armed forces, denied the military would get involved.
"The military will not interfere in the political conflict. The political problem should be resolved by politicians," he was quoted as saying by the Associated Press.
Mr Thaksin has been under pressure for months, over his handling of an insurgency in the south and his control over the media.
But criticism has intensified since his family sold its stake in Shin Corp, the company he built up before he entered politics, last month.
The sale, which netted the family members and others $1.9bn, has angered many urban Thais, who complained the family avoided paying tax and passed control of an important national asset to Singaporean investors.
In a bid to tackle the crisis, Mr Thaksin dissolved parliament on Friday and announced a snap election for 2 April.
But the three main opposition parties have decided to boycott the poll.
Mr Thaksin, who won a landslide victory to win 375 out of 500 seats in last year's general election, may face complaints that his hold on power is unconstitutional if he wins April's poll without the opposition taking part.
Despite his unpopularity among areas and in the disaffected south, his party still retains solid support in the countryside, especially in the north.