Under the terms of the deal, Safra will acquire Rabobank’s 46.07 per cent equity interest – with 68.63 per cent voting rights for SFr7.20 (around $7.73) per A registered share and SFr36.00 per B registered share, to be paid in cash, the firms said in a statement late on Friday.

The announcement was made after stock markets had closed. 

Sarasin will not expand into investment banking after the Safra deal, Sarasin chief executive officer Joachim Straehle told NZZ am Sonntag. The company will remain focused only on private banking, he was reported as saying. While existing clients pulled barely any funds during the sale talks, inflows of new money declined noticeably, he said.

The news of the deal comes at a time when the Swiss banking industry has been assailed by a combination of pressures: attacks on the country's bank secrecy laws, a strong Swiss franc – which has hit revenues booked overseas – and low interest rates. As a result, there has been speculation of consolidation in the country’s banking sector.

There had been widespread speculation that Julius Baer was poised to snap up the share stake. Julius Baer was not reachable for comment at the time of going to press.

As of June this year, Safra Group had aggregate stockholder equity of approximately $12.2 billion and total assets under management of $109 billion.

“For Sarasin, Safra will be a strongly capitalized majority shareholder that will be able to reinforce Sarasin’s established position as an independent Swiss private bank and effectively support and strengthen Sarasin’s strategy and business model under the existing well-recognized brand and management team,” the statement said.

The transaction is subject to approval and clearance by authorities in Switzerland and overseas. Under Swiss law, the closing of the transaction will give rise to a duty to make a mandatory public offer to minority shareholders.

“Sarasin and Safra complement one another strategically in terms of their geographic markets. Both are also highly regarded for their reputation in private banking worldwide, as well as their sustainable and conservative approach to their client’s assets,” the statement said.

“When making its decision, Rabobank wanted to ensure that Bank Sarasin could sustainably maintain its strategic direction and continue its commercial success. Rabobank believes that in Safra it has found an ideal well capitalized, conservative and attractive long-term solution for Bank Sarasin,” the statement continued.

“The sale of its stake in Bank Sarasin will allow Rabobank to concentrate on its strategic priorities and further strengthen its leading role as a universal financial services provider in the Netherlands, as well as pressing ahead with the growth of its international business with food and agribusiness customers,” it said.

Sipko Schat, member of Rabobank’s executive board, said: "Safra's acquisition of Rabobank's shares in Sarasin benefits all three parties. Our successful monetization of our stake demonstrates the enhanced value of Sarasin that has been created and its attractive long-term potential.”

Safra Group, which owns a number of banking businesses, includes Bank Jacob Safra, based in Geneva.