In a move that may explain why GlaxoSmithKline last week turned thumbs down on bidding for Pfizer’s consumer drugs business, the UK’s largest drugmaker has announced plans to buy Novartis’ 35.6% stake in the companies’ consumer joint venture.

The jv was created in 2015 as part of a multibillion dollar swap arrangement that saw GSK transfer its cancer portfolio to Novartis in exchange for the Swiss drugmaker’s vaccines portfolio while the two combined their consumer drugs assets.

In the deal planned to be completed this summer, GSK will pay £9.2 billion ($13 billion) for the shares, considerably less than the $20 billion it potentially would have had to pay for the Pfizer portfolio. Some industry watchers speculate that the company has enough cash to do both deals if it wants. Others think it will take a pass on Pfizer in any case.

The value of the Novartis put option was £8.6 billion at the end of 2017, according to GSK’s financial statement. This represents an undiscounted value of £8.9 billion assuming completion of the option in mid-2018. The drugmaker said its board therefore believes the negotiated price is consistent with the original shareholder agreement.

As of Dec. 31, 2017, GSK said the value of the joint venture’s gross assets represented by Novartis’ stake was £5.9 billion, while the Swiss company’s share of adjusted operating profit was £494 million.

In announcing the buyout plan, Glaxo CEO Emma Walmsley said it “addresses one of our key capital allocation priorities” and will allow the company’s shareholders to “capture the full value of one of the world’s leading consumer health businesses.”

The buyout will also remove uncertainty about the future of the joint venture, the CEO said, as the original jv agreement gave Novartis an option to hand its stake back at any point between March 2018 and the year 2035.

Walmsley revealed also that GSK’s management is conducting a strategic review of other parts of its portfolio that may no longer be of strategic interest. These could include malted milk manufacturer Horlick’s, along with other nutrition products. Horlick’s had sales of £550 million in 2017, for the most part in India.

The proposed transaction, which is to be structured as a cancellation of Novartis’ shares, is subject to approval by GSK shareholders at a general meeting. Walmsley said the board will recommend a vote in favor of the transaction, with a provision that it can be withdrawn for fiduciary reasons or governmental orders restraining or prohibiting it.

Other provisions of the buyout pact stipulate that it may be terminated if agreed in writing between the two sides. GSK said this could be the case if the agreed $200 million break fee has been paid and there has been no shareholder vote approving the transaction within eight weeks. Additionally, the rules call for the transaction to be concluded by the end of December 2018.

For Novartis, CEO Vas Narasimhan said GSK’s cash offer represents “attractive value.” Remarking that “the time is right” for the Basel-based pharmaceutical giant to “divest the non-core asset at an attractive price,” he said the proceeds from the sale will strengthen the company’s ability to allocate capital to grow its core businesses and, among other things, pursue bolt-on acquisitions.

In conjunction with the offloading of its jv stake to GSK, analysts speculated once again that the time might also be right for Novartis to shed its 6% stake in Swiss rival Roche. This is estimated to be worth more than $14 billion.

Novartis has already announced plans to divest its Alcon eyecare business, seenin financial circles as worth more than $25 billion. Any action on the business has been delayed until 2019, according to reports.