ALBANY – Smokers and other critics of Mayor Bloomberg’s proposed cigarette tax hike say it wouldn’t persuade New Yorkers to quit but will convince them that they should do their cigarette shopping online.

Mr. Bloomberg on Monday said he will propose in his budget a tax increase of 50 cents on a pack of cigarettes. The hike would push the city’s tax to $2 and the combined city and state tax to $3.50, the highest total in the nation. When Mr. Bloomberg became mayor, the city’s cigarette tax was 8 cents.

Opponents of Mr. Bloomberg’s plan are predicting that New Yorkers will find a way to avoid paying the tax, just as the mayor said New Yorkers would evade the sales tax on clothing purchases that Governor Pataki is imposing in his new budget. “Anybody with a computer can avoid the tax,” the president of the New York Association of Convenience Stores, Jim Calvin, said. He said more New Yorkers would purchase their cigarettes from online Indian stores.

Mr. Bloomberg said his campaign against smoking has driven down the number of smokers in the city and has saved lives. In June, his administration released telephone survey data that it said showed that the number of smokers in the city has sharply fallen since Mr. Bloomberg took office. A spokesman for the mayor said the $1.42 tax hike imposed in 2002 has increased revenue by $120 million annually.

Mr. Bloomberg also said it’s become increasingly “difficult” for New Yorkers to evade taxes on cigarettes. Attorney General Eliot Spitzer has tried to clamp down on the tax-free cigarette market, pressuring major credit card companies and mail carriers not to do business with the dealers. A retired New York City police officer who has campaigned vigorously against the mayor’s anti-smoking measures, Audrey Silk, said the mayor is treating smokers as if they were “sub-human.”

Mr. Bloomberg’s plan would require approval from the state Legislature.