UBS Group's (UBS) proposed capital requirement changes face continued uncertainty after Swiss lawmakers postponed an interim vote, multiple outlets reported Tuesday.

The Economic Affairs and Taxation Committee of parliament's upper house did not vote Tuesday and will resume deliberations Aug. 31, the reports said, citing a parliament spokesperson.

Committee president Erich Ettlin said lawmakers discussed allowing UBS to meet part of its capital requirements using AT1 bonds instead of costlier capital forms, though changes would need international market acceptance, according to the reports.

The delay postpones the first indication of how lawmakers plan to alter a proposal that could require UBS to hold about $20 billion more in high-quality equity capital, according to Bloomberg.

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