ZURICH, Dec 19 (Reuters) - Cevian Capital has taken a 1.3% stake in UBS, worth around 1.2 billion euros ($1.31 billion), the activist investor group said on Tuesday, betting on a two-fold recovery of its shares following the takeover of Credit Suisse.

UBS shares have risen by 47% this year, outpacing the Swiss market index, which has risen by 4%.

The bank declined to comment on Tuesday.

Cevian, which said in the statement that it is often called "constructive activist", said its strategy is to help companies to be more competitive over the long term and "typically" it works with the support of other owners and stakeholders.

The stock, which closed on Monday at 25.35 Swiss francs, has the potential to reach 50 francs, Cevian managing partner Lars Forberg said.

Artisan is another activist with a shareholding in UBS, according to LSEG data.

"The board and management team are doing an excellent job integrating Credit Suisse and we have been impressed by their commitment to further improve UBS," Forberg said.

The activist investor is not seeking a board seat at UBS, according to the Financial Times, which cited people familiar with Cevian's strategy.

A spokesperson for Cevian declined to comment.

"Strengthened by the acquisition, UBS is the largest global wealth manager with unique market positions and financial strength," Forberg added in his statement.

"If the valuation gap to Morgan Stanley at 2x price to tangible book is closed, the UBS share is worth CHF 50."

Cevian manages more than $14 billion. The UBS stake would account for up to 9% of its portfolio, according to Reuters calculations.

Its most significant current investments include stakes in ABB, CRH, Nordea and Rexel.

($1 = 0.9156 euros) (Reporting by John Revill and Andres Gonzalez, Editing by Linda Pasquini and Louise Heavens)