Romeu, 21, was brought to the Blues from Barcelona by Andre Villas-Boas in 2011, and was starting to make an impression at Stamford Bridge until rupturing his cruciate knee ligament in December.
The Spain Under-21 international was ruled out for the rest of the campaign, having to undergo rehabilitation, but returned to light training in April, before featuring in a charity match in memory of former Espanyol captain Dani Jarque last month.
But while the La Liga club are keen on acquiring Romeu’s services, Chelsea boss Jose Mourinho wants to assess the full extent of the club’s squad upon the resumption of pre-season training on July 8.
And the Portuguese is likely to include the former Barca player on the Blues’ tour of the Far East, which starts the following week.
However, Mourinho may opt to take up Celta’s offer and allow Romeu to gain regular first-team football.
The ex-Real Madrid coach is also likely to include winger Kevin De Bruyne in his plans for next season, despite Borussia Dortmund still hoping to sign the Belgian on a permanent deal.