OneSavings Bank, a new lender aiming to challenge UK's "Big Four", said first-quarter net loans and advances grew by £455 million, helped by its purchase of a portfolio of UK-based second-charge mortgages.

The bank said it expected net interest margins ahead of expectations, helped by the portfolio buy and the absence of competitive price pressure in the year to date.

"We have seen an encouraging increase in new business opportunities at attractive margins and our capital position remains solid," chief executive Andy Golding said.

The lender said it continued to see attractive opportunities for organic growth and would balance opportunities to maximise shareholder returns.

OneSavings Bank, formed following the recapitalisation of Kent Reliance Building Society by US private equity group JC Flowers in 2011, said in March that it was open to takeover offers and expected more consolidation among smaller banks after more than doubling its annual profit.

Mr Golding said the bank was not experiencing pressure on margins despite an uncertain political backdrop.