Credit Suisse posted Thursday a net loss of 2.9 billion francs ($2.9 billion, 2.6 billion euros) for 2015 as it wrote down the value of its assets and booked charges as Switzerland's number two bank seeks to overhaul its business.

The bank's new boss Tidjane Thiam announced last year the bank would axe thousands of jobs and raise billions in fresh capital as it strengthens its balance sheet and pivots its focus towards Asia.

Much of the loss was due to writing down the value of its assets by 3.8 billion Swiss francs in the final quarter of last year "as a result of the new strategic direction, structure and organisation that was announced in October 2015." 

Restructuring charges came in at 355 million francs and 821 million was set aside for litigation.

The bank, which posted a net profit of 1.8 billion euros in 2014, said the "substantial charges... are not reflective of our underlying business performance".

Nevertheless, even its adjusted core results that do not include such charges saw pre-tax earnings fall to 4.2 billion francs from 6.3 billion in 2014.

However Thiam pointed to improving results in three segments on which it is now focusing, in particular its Asia-Pacific and wealth management units.

"This performance was achieved in spite of challenging conditions," said Thiam.

"The fourth quarter of 2015 was characterised by volatile market conditions, pressures on market liquidity, a sharp decline in oil prices, widening credit spreads, continued uncertainty linked to asynchronous monetary policies, and large fund redemptions by market participants affecting asset prices."