BERLIN — Switzerland’s UBS said today that it expects to complete its takeover of longtime rival Credit Suisse as early as next week.

The two Zurich-based banks are uniting in a 3 billion-franc ($3.3 billion) deal that was arranged hastily in March by the Swiss government and regulators after Credit Suisse’s stock plunged and jittery depositors quickly pulled out their money.

The merger was aimed at stemming upheaval in the global financial system after the collapse of two U.S. banks shook confidence in the sector. The takeover will leave UBS as Switzerland’s single banking titan.

UBS said today that it expects to complete the acquisition by as early as June 12. Credit Suisse said it also expects completion as early as next Monday, and that it would be delisted from the SIX Swiss Exchange and the New York Stock Exchange on June 12 or the day after if that happens.

“Completion is subject to the registration statement, which covers shares to be delivered, being declared effective by the U.S. Securities and Exchange Commission, and to satisfaction, or waiver by UBS, of other remaining closing conditions,” UBS said in a statement.

The reputation of 167-year-old Credit Suisse was pummeled in recent years over stock price declines, a string of scandals and the flight of customers worried about the bank’s future.