The Spanish international has been linked with a move away from the RCDE Stadium after racking up an impressive goal tally in 2021/22.
De Tomas netted 17 league goals in Catalonia last season, and he could be tempted by a new challenge in the Champions League.
De Tomas’ release clause is set at €75m, with 20% of a potential sale going to former club Benfica.
Despite the speculation, Espanyol club president Domingo Catoira told reporters there has been no formal offer, prior to their 5-1 preseason loss at Brighton & Hove Albion.
“His performances in these last two years have led us to achieve important goals”, as per reports from Mundo Deportivo.
“He’s always in the rumour mill, but the reality is there have been no offers for him.”
Espanyol take on Napoli in their final preseason game on August 6 ahead of kicking off their domestic campaign at Celta Vigo on August 13.