British insurer Aviva pledged on Thursday to return at least 4 billion pounds ($5.5 billion) to shareholders, sending its shares surging, but activist investor Cevian Capital demanded more.

Cevian, which revealed in June it had built up a near 5% stake in the FTSE 100 company, promptly reiterated that Aviva should return 5 billion pounds of excess capital by the end of 2022.

“The at least four billion pounds excess capital return … is a good start, but … would not be enough to address the overcapitalisation and we expect the company to return five billion pounds by the end of next year,” Cevian partner Niko Pakalén said.

Aviva has raised 7.5 billion pounds from selling eight businesses across the globe since the appointment of Amanda Blanc as chief executive in July 2020.

The life and general insurer, which has its main businesses in Britain, Canada and Ireland, had previously promised a “substantial” capital return.

“We’ve provided guidance earlier than expected … we are accelerating the timing of the capital return,” Blanc told a media call, adding that relations with Cevian were “constructive.”

Shares hit their highest in eight weeks on the news and were up more than 4% at the top of the FTSE 100 index by 1240 GMT. If gains hold, they’d mark their best one-day advance since the beginning of this year.

Aviva said it intended to return the capital by the end of the first half of 2022, starting with an immediate 750 million pound share buyback.

Re-Rating?

JPMorgan analysts said the buyback announcement would likely lead to a re-rating of the stock in the next six months, reiterating their “overweight” rating.

Aviva said it was on track to achieve a targeted 300 million pounds in cost savings in 2022.

The insurer has reduced its property portfolio by 30% this year, generating savings of 20 million pounds, Blanc said, and was also making savings through digitisation.

Cevian has called for at least 500 million pounds in cost savings by 2023.

Aviva reported a 17% rise in first-half operating profit from continuing operations to 725 million pounds, below a company-provided consensus of 781 million pounds.

The insurer said it would pay an interim dividend of 7.35 pence per share, up 5% but below a forecast 7.37 pence.

($1 = 0.7211 pounds) (Reporting by Carolyn Cohn and Huw Jones, additional reporting by Muvija M.)