BOSTON -- The New York Times Co. has threatened to close down the Boston Globe unless the newspaper's unions quickly agree to $20 million in concessions.

The Times, which owns the Globe and Worcester Telegram, made the demands Thursday morning in meeting with leaders of the newspaper's 13 unions. Daniel Totten, president of the Boston Newspaper Guild, the Globe's biggest union, said the unions had 30 days to agree or the paper would be closed.

The possibilities include pay cuts, the end of pension contributions by the company and the elimination of lifetime job guarantees now enjoyed by some veteran employees, said Totten.

"We all know the newspaper industry is going through great transition and loss," said Ralph Giallanella of the union that represents the drivers who deliver the newspaper. "The ad revenues have fallen off the cliff. Just based on everything that's going on around the country, they're serious."

Times management told the unions that the Globe will lose $85 million in 2009, unless significant cuts are made.

Officials with both the Times Co. and the Globe refused comment.

The Globe was founded in 1872 by six Boston businessmen and is the largest daily newspaper in New England. The average daily circulation is 350,605, according to the newspaper. Sunday circulation is 525,959, though sales have dropped sharply in recent years.

The Globe was purchased by the New York Times Co. in 1993.

The Globe has gone through several rounds of staff reduction through buyouts in recent years, including 50 last week.

Since 1966, the newspaper has won 20 Pulitzer prizes, including one for uncovering the Roman Catholic church priest sex abuse scandal in 2003.

The newspaper industry has been battered by both the drop in advertising and the growth of online news Web sites. Hearst Newspapers recently turned the Seattle Post-Intelligencer into a Web-only publication, and Scripps Co. closed the Rocky Mountain News in Denver.

The Christian Science Monitor, which is based in Boston, stopped daily publication last week in favor of online news. Other major papers have filed for bankruptcy.