UK Culture Secretary Karen Bradley told parliament on Thursday that the takeover "potentially raises public interest concerns." She referred the matter to the Competition and Markets Authority for further review.

"The transaction may increase members of the Murdoch Family Trust's ability to influence the overall news agenda and their ability to influence the political process and it may also result in the perception of increased influence," Bradley said.

"I confirm that I am minded to refer to a phase two investigation on the grounds of media plurality," Bradley added.

Murdoch's Fox announced in December it had reached a formal agreement - which would expand the footprint of the media-entertainment group owned by Murdoch - to buy the 61-percent stake in Sky it did not previously own.

Too much power? 

Critics argue that the 11.4-billion pound ($14.7-billion, 12.9-billion euro) deal would give Murdoch too much power in British media. Murdoch's company already owns two of the country's biggest newspapers, The Sun and The Times.

The deal would give 21st Century Fox access to Sky's 22 million customers in the UK, Ireland, Austria, Germany and Italy. The company already offers over 600 pay TV channels, including the UK's Premier League soccer, news and the popular US series "Game of Thrones," which attracts an average of more than 6.5 million viewers per episode.

An earlier attempt to buy Sky was thwarted by the 2011 phone-hacking scandal that rocked Murdoch's British newspapers and led to the closure of the 168-year-old News of the World tabloid.

21st Century Fox is one of the world's largest entertainment companies. It has a large portfolio of cable, broadcast, film, pay-TV and satellite assets across six continents. Sky has a similar offering, with its 24-hour Sky News channel, and internet and telephone services.

In 2014, it changed its name from BSkyB after buying Sky Italia and a majority holding in Sky Deutschland.

Sky reported operating profit of 1.6 billion pounds ($2.1 billion) for the year ended June 30, 2016, on revenue of 12 billion pounds.

jbh/sri (AFP, AP, Reuters)