Adds details, PRA statement

LONDON, Oct 8 (Reuters) - Embattled British bank Metro MTRO.L announced a 325 million pound ($396.5 million) capital raise and 600 million pound debt refinancing on Sunday, after a weekend of urgent talks to secure its future after a volatile week of trading.

Metro Bank said the capital raise comprised 150 million pounds of new equity and a 175 million pound issuance of bail-in debt.

The equity raise was led by Metro's largest shareholder, Spaldy Investments, which is owned by Colombian billionaire Jaime Gilinski. Spaldy will become the controlling shareholder once the transaction completes, Metro said, with a 53% stake.

The bank also said it was in discussions regarding the sale of up to 3 billion pounds of residential mortgages.

The Bank of England's Prudential Regulation Authority said in a statement: "The Prudential Regulation Authority welcomes the steps taken by Metro Bank to strengthen its capital position."

($1 = 0.8196 pounds)

(Reporting by Iain Withers in London, additional reporting by Lavanya Ahire in Bengaluru; Editing by Lisa Shumaker)

((LavanyaSushil.Ahire@thomsonreuters.com;))