Source: Sharecast
According to Sky News, Santander is among the parties which have expressed an interest in a potential deal, months after its boss denied that it was seeking to offload the UK's fifth-largest retail bank.
City sources told Sky on Wednesday that Santander had not tabled a formal offer for TSB, and was not certain to do so.
However, the fact that it has contacted Sabadell about a possible transaction involving TSB suggests that chair Ana Botin may be open again to expanding its presence in Britain's high street banking market, Sky said.
Sky also said that the value that TSB, which was acquired by Sabadell in 2015 from Lloyds Banking Group, might attract in any takeover was unclear.
Sabadell is in the middle of attempting to thwart a hostile takeover by rival Spanish bank BBVA, with a disposal of TSB said to be on the cards regardless of whether or not that bid is successful.
NatWest, Barclays and HSBC have also been touted as potential suitors for TSB, although at least two of those three banks are thought to have little interest in bidding.
Sabadell confirmed on Tuesday that it was exploring a potential sale of TSB.
In a brief statement following widespread media reports, the lender said it had received "preliminary non-binding expressions of interest for the acquisition of the entire share capital of TSB" and confirmed it would weigh up any potential binding offer.