A major policy flap that ultimately could delay the approval of new cable television franchises in dozens of areas across the country is brewing between the major lobbying arms of the industry and the nation's cities.

The National League of Cities is threatening to urge more than 60 of its 950 member cities to begin a "national moratorium" on ongoing and complex negotiations between municipal governments and the competing companies seeking cable outlets.

The target of the league's campaign is the National Cable Television Association, the leading industry lobbying group. The NCTA has announced its support for legislation before the Senate Commerce Committee that would deregulate many facets of cable television and, in the league's view, limit the local role in considering competing franchises. i

What the League of Cities is so angry about is that officials in some cities, in addition to league officials, thought they had a working agreement with the NCTA to begin producing a new code for these lengthy and highly politicized negotiations on franchise awards. Those talks began in May -- a month before the content of the Senate bill was announced -- and now appear dead so long as the cable group supports the deregulation effort.

"Your city is one of more than 60 areas where major cable franchises are in some stage of local negotiation or renewal at this time," Alan Beals, executive director of the league, said in a letter prepared yesterday of city executives.

"Because we must now question the good faith of the cable industry and the sincerity of NCTA's interest in developing franchising standards that are in the public interest, the League believes cities such as yours are in a postion to send a clear message to the cable television industry," the league wrote.

The threat of league advocacy of the moratorium -- which Beals said in his letter is a subject being given "serious thought" -- is clearly a major power play and a demonstration of the depth of the league's feelings about cable deregulation.

Among the municipalities studying cable television and preparing for franchising are Montgomery, Prince George's and Fairfax counties in suburban Washington, and Miami, Boston, Detroit, and Milwaukee. Those franchises are worth millions of dollars to their potential owners and could broaden dramatically the programming available in those cities.

The legislation includes the bitterly debated provisions to deregulate many facets of the telecommunications industry and restructure the operations of American Telephone & Telegraph Co., and the NCTA-NCL fight is just as bitter. A telecommunications bill before a House committee does not include specific provisions concerning cable television deregulation.

And the response of the cable industry group was just as vitriolic as the league's threat. "It is terribly unfortunate and unfair to punish consumers of their own misinterpretation of the legislation," Thomas Wheeler, president of the NCTA, said yesterday in an interview.

"The projects we were jointly working on we intend to carry on with or without the League fo Cities," Wheeler said. "The issues in the legislation are really separate from the issues in the franchising process."

The NCTA maintains that the League of Cities has misinterpreted the legislation and that the Senate bell -- whose five sponsors include Howard Cannon (D-Nev.), the committee's chairman -- bars rate regulation of pay television or the sale of ad or program time on cable television but maintains local regulation of basic consumer rates. Yet the legislation would prohibit a government from forcing a franchise to unilaterally provide access to government or the public.

The league, however, sees the bill differently. "Because local governments usually control the use of public streets -- where cable operators must string their cables -- and are the level of government closet to the people, they are the logical franchisers of cable television," Beals said in a letter to Wheeler two weeks ago.

The bill would "prohibit the requiring of local program origination and public access and the establishment of subscriber fees, and authorize the FCC to establish franchise fee ceilings," Beals wrote.