Insider sources told the Financial Times that the first agreement will see Santander take $4.3 billion worth of US car loans from HSBC, with the second involving the purchase of 318 bank branches from RBS.
The latter deal will be made up of a premium of around Â£100 million ($159 million), with the net asset value of the portfolio to be finalized when the transaction closes, which could take around 18 months.
At the moment, the value of the agreement could be as much as Â£1.5 billion, but this may change a considerable amount by the time the deal goes through.
Last month, it was reported that Santander is planning to float around 20 per cent of its UK operations on the London Stock Exchange to help with funding its planned acquisitions.
By Tony Aynsley