A British production company has agreed to buy MTM Entertainment Inc., the TV and movie company co-founded by actress Mary Tyler Moore, in a deal worth around $325 million, according to a report published today.

Television South PLC, known as TVS, said it could neither confirm nor deny the report in the Financial Times, but said its chief executive James Gatward would make a statement at a news conference here Wednesday.The Financial Times said the deal was struck in London on Thursday after all-night negotiations, prompting a suspension of trading in TVS shares on the London Stock Exchange.

MTM, a private Los Angeles company which takes its name from Miss Moore's initials, had planned a $100 million initial public stock offering last year but withdrew these plans after the October stock market crash.

At that time, the company was valued at around $450 million and had after-tax profits of $26.1 million in the 1987 financial year, down from $30.6 million the previous year, according to the Times.

Since MTM was founded in 1970, it has produced about 30 television series and more than a dozen made-for-TV movies. Among its hit TV series have been "Hill Straeet Blues" and "St. Elsewhere," which have a large audience in Europe.

In addition, MTM develops and produces theatrical movies and operates a record and music publishing company, MTM Music Group of Nashville, Tenn.

TVS, although relatively small, screens its productions in southern England, the most prosperous area of Britain.

TVS productions are aired by Independent Television, Britain's two-channel national commercial network.

The non-commercial British Broadcasting Corp. runs the other two channels.

TVS showed a pre-tax profit of 21.8 million pounds, or about $37 million, in the fiscal year ending last October.

Revenue totaled 171.9 million pounds, or about $292.2 million.

The Financial Times said TVS has more than 25 million pounds, or $40 million, in cash and will finance the deal by issuing stock underwritten by the British merchant bank County NatWest.

It said the deal would give TVS production capacity in the United States, potential access to the U.S. networks "and a library of programs to sell across Europe to television stations and cable and satellite."