UPDATE 1-Swiss competition watchdog probes suspected payment systems boycott

* WEKO probes a suspected boycott of Apple Pay, Samsung Pay

* Targets of probe include Swiss units of Credit Suisse, UBS

* Credit Suisse: Convinced allegations will prove unfounded (Adds further details, comments by Credit Suisse, Postfinance)

ZURICH, Nov 15 (Reuters) - Switzerland's competition watchdog WEKO said it had searched offices of Swiss financial companies including Credit Suisse and UBS as it probes a suspected boycott of mobile payment solutions such as Apple Pay and Samsung Pay.

The probe targets Aduno Holding, Postfinance, Swisscard AECS GmbH and Swiss units of Credit Suisse and UBS, WEKO said on Thursday.

The competition authority is investigating whether the financial companies colluded not to use international mobile payment solutions, in favour of a Swiss alternative.

"There is the suspicion that the companies agreed not to make their credit cards available for use with Apple Pay and Samsung Pay, in order to favour the Swiss solution TWINT," WEKO said in its statement.

Some of the companies targeted in the probe said the regulator's accusations were without merit.

"We are surprised about this investigation and are convinced that the allegations will prove to be unfounded," Credit Suisse said in a statement.

Credit Suisse added that it offers Swiss consumers access to Apple Pay and Samsung Pay through its 50 percent subsidiary Swisscard and has also been in talks with Apple, Samsung and Google over how their solutions can be used.

Postfinance, the financial unit of Switzerland's postal service and one of the country's largest banks, also said it was convinced it did not breach Swiss cartel law and said it was cooperating with the WEKO probe. (Reporting by John Miller; Editing by Simon Cameron-Moore and Maria Sheahan)