ZURICH (Reuters) -The Swiss National Bank called on Tuesday for a review of bank capital regulations, saying Switzerland needed rules that recognise that UBS has become a bank with even more systemic importance following its takeover of Credit Suisse.

In its annual report, the SNB also said it would accept some forms of credit as collateral from banks wanting to access cash in an emergency, a significant move that is designed to ensure banks don't run out of cash in a crisis.

Last year the SNB said Credit Suisse's lack of collateral accelerated the bank's collapse.

The Swiss central bank had signalled its intention to enlarge the pool of assets that can be pledged to include credit such as Lombard and commercial loans, Reuters reported on Monday.

Broadening the range of assets could enable UBS to significantly expand how much it could tap in an emergency. As of the end of 2022, UBS had $154 billion of Lombard loans on its books.

The SNB also said that banking regulation should be overhauled and banks' financial positions strengthened to avoid future crises.

"The systemic importance of UBS has increased considerably with the acquisition of Credit Suisse. A review needs to be made as to whether the progression takes adequate account of this increase in systemic importance," the SNB said.

The bank's report comes as the Swiss government is preparing its own recommendations on how to deal with banks that are "too big to fail", expected to be published next month.

Last year, the SNB played a major role in the state-sponsored rescue of Credit Suisse, making over 200 billion Swiss francs of liquidity available to ease its takeover by UBS.

It also took flak, however, from some critics who argued Credit Suisse could have been saved if the SNB had acted sooner.

The SNB highlighted a need for action in two areas on capital regulation - AT1 bond instruments and the strength of common equity tier 1 capital ratios.

The central bank also said it was important to ready a broad range of options for the resolution of a systemically important bank.

In the event of a liquidity crisis, it is vital that market regulator FINMA "is able to enforce resolution measures in a timely manner and with sufficient legal certainty", the SNB said.

In order to stabilise a systemically important bank in time, the SNB said that the "early intervention tool kit" should be expanded to include market-based and forward-looking indicators.

The SNB said it is participating at national and international level in the debate about regulatory adjustments.