Swiss banking giant UBS voluntarily put an end Friday to the state and central bank support that smoothed its takeover of stricken Credit Suisse, saying they were no longer necessary.

UBS agreed to buy its rival in a 3-billion-franc ($3.5 billion) fire sale hastily arranged over a March weekend by Swiss authorities afraid that a weakened Credit Suisse would go bankrupt.

UBS was granted up to 9 billion francs for protection against any losses incurred selling certain Credit Suisse assets, along with 100 billion Swiss francs in liquidity assistance provided by the Swiss National Bank (SNB).

These loans ensured that both banks had sufficient liquidity to carry out the takeover.

It also assured protection for UBS against the risk of extreme losses, as UBS had "very limited" time to study Credit Suisse's assets during takeover negotiations.

Having now examined the assets, UBS concluded that the government support is no longer needed and asked for a "voluntary termination" of the agreements as of Friday.

UBS will pay 40 million francs in compensation for the measures.

The bank also announced that Credit Suisse had fully repaid the additional liquidity support loans granted by the central bank.

The measures "were necessary due to the acute crisis of confidence at Credit Suisse," the SNB said in a statement Friday.

The liquidity assistance amounted to 168 billion francs, the SNB said, emphasising that it "has been repaid in full".

"With the acquisition of Credit Suisse by UBS, a solution was found to secure financial stability and protect the Swiss economy in this exceptional situation," the SNB said.