Chelsea midfielder Conor Gallagher has landed back in England as his proposed transfer to Atlético Madrid remains in limbo, sources have told ESPN.

The 24-year-old has agreed personal terms on a 34 million ($43.7m) deal and travelled to the Spanish capital several days ago in anticipation of completing his move, only for a last-minute hitch to complicate the situation.

Gallagher passed a medical at Atlético but was subsequently told the move is on hold as the transfer the LaLiga club needs to make to finance his transfer had collapsed.

In separate talks, Chelsea were expected to sign Atlético forward Samu Omorodion but negotiations ended.

Conversations have instead turned to whether an agreement can be reached between the two clubs for João Félix, who spent six months on loan at Stamford Bridge in 2023.

Gallagher had been using Atlético's facilities to maintain his fitness while awaiting confirmation of his move but he has now returned to London with no agreement imminent following Omorodion's move not materialising.

It is possible that a deal for Omorodion could be revived or Chelsea could yet reach an agreement for Félix but Gallagher's future is uncertain until either scenario is clarified.

Sources have told ESPN that Gallagher is likely to train away from Chelsea's first-team squad at Cobham while the situation is resolved.

The England international has turned down Chelsea's offer of a new contract -- his existing agreement has less than 12 months left to run -- while he also previously rejected a move to Aston Villa.