American Telephone & Telegraph Co. yesterday proposed higher charges for extensions to a bulk-rate, private-line service called Telpak, as required by the Federal Communications Commission.

The new rates, scheduled to take effect Jan. 23, apply primarily to national news wire services - including the Associated Press, United Press International, Reuter and Commodity News Service - and 150 other large users of communications services.

Telpak allows a customer to purchase 60 to 240 private lines at one time at bulk rates. Circuit extensions, called Telpak "end links," must be priced on the same basis as similar private services, the SCC ruled in 1975.

The regulatory agency's order was appealed by the American Newspaper Publishers Association and appealed by news-gathering organizations, who cited a traditional break in prices for dissemination of information. But the U.S. Court of Appeals upheld the FCC order last summer.

AP ans UPI have estimated that the new charges would increase their annual Telpak tariffs by $4.3 million. Overall, an AT&T spokeman said yesterday, the higher charges would bring in $12 million in new annual revenues for the Bell System: if current services are maintained, the rate increase would be 2.7 per cent, AT&T said.

The telephone company is attempting to end Telpak service altogether. AT&T objects to a federal court decision last summer upholding an FCC order that private-line customers be permitted to resell or share their Telpak sevices with others.