FILE PHOTO: Britain's Deputy Leader of the Labour Party Tom Watson sits in the conference hall before Labour Party leader Jeremy Corbyn delivers his keynote speech at the Labour Party Conference in Liverpool, Britain, September 26, 2018. REUTERS/Phil Noble

LONDON (Reuters) - Digital tech firms are too big and Britain’s opposition Labour Party would create a dedicated technology regulator to prevent market abuse and look at breaking up monopolies like Facebook, the party’s deputy leader will say on Wednesday.

The digital revolution has spawned a handful of U.S.-based technology companies since the 1990s that now have a combined financial and cultural power greater than most sovereign states.

Tom Watson will lay out plans which include creating a regulator, creating a Digital Bill of Rights and giving social media firms a broad legal duty of care to protect users.

“The scale of the largest companies is rightly the subject of scrutiny. We should take seriously the calls to break them up if it is in the public interest,” Watson is expected to say.

Facebook in particular has come under scrutiny over its use of data. Concerns about its ability to safeguard user data have sparked a government lawsuit in the United States, while it has been criticized by lawmakers around the world.

Shares have been hit by investors concern about snowballing legal and regulatory efforts over its data use polices.

Labour did not set out in detail how a British regulator might attempt to break up some of the most powerful companies in the world, almost of which are based outside the United Kingdom.

In a interview with BBC radio, Watson cited Facebook’s purchase of Instagram an example of a merger that concentrated user data in a dangerous way.

“Our competition laws are not fit for the age of big data,” he said.