UBS Group (UBSG.S) said on Wednesday it would buy back 2.75 billion euros ($2.96 billion) worth of debt it issued less than a week ago, seeking to boost confidence among investors rattled by its $3 billion rescue of rival Credit Suisse at the weekend.

The bonds in question, senior unsecured bail-in notes that were issued on March 17, include the 1.5 billion-euro 4.625 per cent fixed rate note due March 2028 and the 1.25 billion-euro 4.750 per cent fixed rate notes due March 2032, UBS said in a statement.

Since its government-backed rescue of Credit Suisse, UBS has seen the value of its shares and bonds gyrate wildly. UBS stock fell by as much as 17 per cent after markets opened on Monday, only to close 35 per cent higher than those lows the following day.

The yield on its 7 per cent additional tier dollar bond – a form of bail-in note – jumped to a record 29.8 per cent at one point on Tuesday, from below 10 per cent just a week ago, according to Refinitiv data. Those bonds were last yielding 18.7 per cent.

Part of the rescue package for Credit Suisse involved the company writing down to zero the value of $16 billion in AT1 bonds, meaning those bondholders got nothing, while equity holders at least got the value of the share offer.

UBS shares were last flat on the day at 19.42 Swiss francs ($21.05), having risen by as much as 3.6 per cent in very early trading. ($1 = 0.9285 euros)

($1 = 0.9224 Swiss francs)