In this July 30, 2017 photo, the logo for CK Hutchison Holdings Ltd is displayed atop the Cheung Kong Center building, which houses the company's headquarters, in Hong Kong, south China. (PHOTO / BLOOMBERG)

HONG KONG/LONDON - Vodafone and CK Hutchison are in the final stage of agreeing to merge their British operations, with an announcement expected as soon as Friday or early next week, three sources have told Reuters.

Shares in Vodafone jumped 3 percent on the news on Wednesday.

Vodafone will own 51 percent and Hutchison 49 percent of the combined group, which could be worth around 15 billion pounds ($18.6 billion) including debt, in line with an announcement made by Vodafone in October, one of the sources said

Vodafone will own 51 percent and Hutchison 49 percent of the combined group, which could be worth around 15 billion pounds ($18.6 billion) including debt, in line with an announcement made by Vodafone in October, one of the sources said.

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The respective stakes would be achieved by adjusting the ownership of debt rather than exchanging cash, the companies said in October.

Talks about the deal to create Britain's biggest mobile operator have been protracted. Hutchison's chief financial officer Frank John Sixt said last month that getting it over the line was proving to be "extremely difficult".

Vodafone's new Chief Executive Margherita Della Valle is under pressure to agree deals in major markets to improve the pan-European and African operator's performance.

Her predecessor Nick Read identified Britain as one of four markets that would benefit from consolidation, but a lack of progress frustrated shareholders, leading to him stepping down in December.

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The tie-up will create Britain's biggest mobile operator with about 27 million customers, overtaking BT's EE and VM O2, owned by Telefonica and Liberty Global.

The deal will face intense scrutiny from regulators who have previously opposed deals that reduce the number of networks in major markets from four to three.

Vodafone and Hutchison have argued, however, that the deal would benefit consumers by creating a network with the scale to roll out full 5G and expand broadband connectivity.

Hutchison has said it does not cover the cost of its capital in Britain, potentially hampering its ability to invest.

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Sources told Reuters in April that the companies could commit on network investments as part of their approach to regulators.

Hutchison and Vodafone declined to comment.