Sovereign Bancorp, the second-biggest US savings and loan company, is poised to raise about $1bn (£511m) in fresh capital from a group of investors that may include Grupo Santander of Spain.

The deal, which could be announced next week, would make Philadelphia-based Sovereign the latest in a growing line of struggling US banks seeking to raise capital to offset growing losses on mortgage, home equity, automotive and other types of consumer loans.