Barcelona have began to accept that a deal for Nico Williams this summer is looking unlikely and are assessing other options, including Dani Olmo, sources have told ESPN.

Athletic Club winger Williams, 22, is Barça's top target and president Joan Laporta suggested his 58 million ($62.73 million) release clause is affordable, but a combination of reasons have complicated a potential transfer.

Sources insist paying the clause is not a problem, as Barça have the money available, but they are unable to guarantee Williams will be registered with LaLiga immediately.

They remain in excess of their LaLiga-imposed spending limit and until they bring in cash through transfers or new revenue streams, they are limited on what they can spend by the league.

The pressure being put on Williams, who excelled for Spain as they won Euro 2024, to stay at Athletic -- where he plays alongside his brother, Iñaki -- for another season, coupled with interest from Paris Saint-Germain, are further motives that lead Barça to believe a deal won't be possible.

Sources close to PSG believe Williams wants to join Barça but that the LaLiga side can't do a deal right now. They have not made an offer but have held talks with his camp and would want him this summer as they look to re-build following the loss of Kylian Mbappé.

Laporta said there will be "good news" soon and Barça's financial position is "improving" at new coach Hansi Flick's presentation last week, but until that news is confirmed they have their hands tied in the transfer market.

The Catalan club still need to register Iñigo Martínez and Vitor Roque -- who were only registered until the end of last season -- while defender Ronald Araújo will not be registered with LaLiga for now due to his long-term injury. He's not expected back until November after undegoing surgery on a hamstring problem.

Barça believe a deal for Olmo could be more achievable, sources say. The versatile forward is open to a return to the Catalan club, who he left as a 16-year-old to move to Croatia, but a deal must be struck with RB Leipzig first.

Olmo's 60 million ($64.89 million) release clause expired on July 20 but sources close to the player have told ESPN the German club will honour a verbal agreement to let him leave if a club is prepared to pay around that amount this summer.

However, there is currently a standoff over that fee, with Barça hopeful of agreeing a much lower initial fee with the rest made up in performance-related add-ons.

Sporting director Deco has remained in Barça to work on possible signings, as well as departures, with the rest of the club's hierarchy travelling to the United States for the club's tour this week.

A big-money exit would aid Barça's bid to strengthen the squad this summer, but sources say nothing is likely to happen imminently.

Araujo's injury has ruled out a transfer, with ESPN revealing earlier this year Barça would listen to offers for the Uruguayan defender, while Frenkie de Jong and Raphinha keen to stay and fight for their places. Brazil striker Roque is another who could leave.

Clément Lenglet and Oriol Romeu will also be allowed to depart, but neither will bring in a big fee.

Meanwhile, the club continue to work on filling the 40 million ($43.26 million) hole created by the German company Libero's non-payment for a stake in the Barça Vision, the club's in-house production company which also is also working on Web3 and AI projects.

Information from ESPN's Julien Laurens contributed to this report.