UBS laid down a $1 billion offer on Sunday to buy Credit Suisse, as Swiss authorities plan to amend a law requiring a shareholder vote on the matter, in an attempt to secure the deal before markets reopen on Monday, the Financial Times reported.

The acquisition will be worth just a fraction of Credit Suisse's closing price on Friday evening, just over $8.7 billion - despite a $54-billion lifeline secured by the Swiss National Bank SNB.

Swiss laws typically require UBS to engage in consultations with its shareholders over six weeks before making an offer, however, the emergency at hand pushed the government to skip the consultation period and a shareholder vote, FT said earlier. 

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Switzerland's biggest bank, UBS, has been actively running against the clock during the weekend to finalize the takeover of crashing Credit Suisse before Monday, and the troubled bank's stock shares fell even more dramatically until deemed insolvable.

The Swiss government has been urging UBS to take the deal in just few days - which usually would take months considering the volume of the bought entity - in efforts to avoid a widespread panic among the banking systems and prevent a ripple effect impacting other financial institutions.

Timely negotiations over the buyout have included the bank's board, the Swiss government, the central bank SNB, and financial regulators.

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According to Blick newspaper, the takeover will take place on Sunday in Bern, during a meeting between the bank's top executives and government officials.

"When the stock market opens on Monday, Credit Suisse could be a thing of the past," the newspaper said, explaining as to why the Swiss government has been rushing to secure this deal over mounting pressure from the country's largest economic and financial partners.

Bloomberg reported on the matter, citing unnamed sources, that UBS will demand publicly stated guarantees to cover legal expenses and even potential losses.

- The unthinkable becomes true - 

Swiss newspaper SonntagsZeitung called it "the merger of the century".    

"The unthinkable becomes true: Credit Suisse is about to be taken over by UBS," the tabloid said. The government, Swiss Financial Market Supervisory Authority FINMA and the SNB "see no other option", it added.    

"The pressure from abroad had become too great -- and the fear that the reeling Credit Suisse could trigger a global financial crisis."  

- Not too big -

Credit Suisse is among the largest 30 banks in the world - dubbed as Global Systemically Important Banks - that were previously considered to be too big to fail.   

"We are now awaiting a definitive and structural solution to the problems of this bank," France's Minister of Finance Bruno Le Maire told Le Parisien newspaper. "We remain extremely vigilant."    

The Financial Times reported that Credit Suisse depositors withdrew around 10 billion Swiss francs ($10.8 billion) from their accounts in just one day last week.