However, the new lotteries will not be ready in time for the June 16 draw.

"We have to consult the Council of State and we have to listen to the opinions of people," Chalongphob said, adding that a survey would be conducted early next month.

One option is for the Government Lottery Office (GLO) to issue two- and three-digit tickets with pre-printed sequential numbers. Each ticket will cost Bt40 and buyers have to choose from the numbers available. The winning tickets will be determined by the prize-winning number in the GLO's six-digit lottery. Holders of tickets with the number corresponding to the final two digits of the winning six-digit number will win Bt2,000, and those holding tickets with the final three numbers will win Bt20,000.

"There will be two jackpot prizes, each worth Bt20 million," Chalongphob said.

These tickets would also have a chance of winning 400 special prizes of Bt300,000 each, he added.

The jackpot and special prizes would be based on the serial number of the tickets, he said.

Chalongphob said 40 million tickets would be issued for each draw, with the prize money comprising 60 per cent of total sales.

"It's possible some tickets with numbers like 00 and 000 won't be able to find buyers, so we will have to think about setting up a fund for vendors to return unsold tickets," he said.

The second option is to issue tickets with empty boxes for buyers to fill in their chosen two- or three-digit number. The tickets would be priced Bt20, Bt50 and Bt100 each, with the prize money increasing with the value of the ticket.

"The prizes will also vary because buyers of the same winning number will have to share. If a popular number wins, each will get less money. If a rarely chosen number wins, the prize will be bigger," Chalongphob explained.

There would be special prizes and jackpots similar to those of the first option.

Chalongphob said the third possibility was to sell two- and three-digit tickets through vending machines, but this would likely trigger criticism and have many adverse consequences.

"Critics will say this could mislead people and put ticket vendors out of work," he said, adding that there would also be legal ramifications because it would mean a joint venture between the private sector and the government.

He did not say whether the ticket numbers would be pre-printed or could be chosen, or what the prizes would be.

Chalongphob said the Council of State would examine the options. "What we do next depends on legal interpretations by the Council of State," he said.

If the council rules all the options illegal then the government will review the possibilities, he said.