Julen Lopetegui has been heavily backed in the transfer market since being appointed as the replacement for David Moyes.
A total of eight senior additions have been made by the Hammers, leaving them in a position where they need to reduce their outgoings in order to further bolster their squad.
With Guido Rodriguez having arrived on a free transfer from Real Betis, the perception was that the midfield options were solidified until it emerged earlier in the week that James Ward-Prowse was available to leave for the right price.
Nottingham Forest are seemingly on the brink of completing a deal for the England international, initially on a season-long loan deal.
Lopetegui moves for Soler
As such, a spot will open up in the East Londoners' squad and Lopetegui has seemingly chosen to sign Soler as the England international's replacement.
According to transfer expert Fabrizio Romano, West Ham have agreed terms with PSG for the Spaniard to make the switch to the London Stadium on loan.
The two clubs are are also said to have agreed terms over a buy option of €20m (£16.82m) at the end of the season.
Soler has been at Parc des Princes for the past two years, making a total of 63 outings in all competitions.
While eight goals and eight assists have been contributed during those appearances, the 27-year-old has not featured during the early part of the campaign.