Barcelona tried to get Ousmane Dembele to leave in January, but they have approached him about a new contract.
The club contacted Sissoko and Lichtsteiner on Tuesday to propose reopening negotiations.
Talks are expected to take place in the coming weeks, with them agreeing to listen to Barcelona's offer.
It's a significant change of fortune after Barcelona tried to force the France winger out in January amid a stalemate over an offer that included a significant pay-cut, and was made at the same time the club were signing a new player.
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Dembele is enjoying his football again, and he has some of the best attacking stat in Europe. He has the best assists-per-minute ratio in the top five leagues this season, the most assists in Europe since the turn of the year, and the second-most in La Liga.
Barcelona vice-president Rafa Yuste said last week that if Dembele continues to feel comfortable, then we can meet his agents and he could stay with the club.
Barcelona are hoping that a strong relationship with Raphinha's agent will help them get him to join them.
Sky Sports News reported on Tuesday that the club was interested in Deco and that Joan Laporta confirmed that in an interview with Catalan radio station RAC1.
Laporta said that Raphinha is a great player. We have good reports of him. Deco gives us details so that we don't make mistakes. It has helped us a lot.
Raphinha is yet to sign the terms of his new contract, which has been ongoing since last year.
There was a lot of interest from other teams in January, but he didn't move.
His future is expected to be back on the agenda at the end of the season regardless of whether or not he stays in the league.
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Barcelona would have to pay a transfer fee to get Raphinha because his current deal runs until 2024.
They expect to have a limited amount of cash available to them for some purchases this summer, and hope that they will be able to top it off with player sales, after their serious financial plight was alleviated somewhat by a new sponsorship deal with Spotify.
With eight games left, Jesse Marsch's side are seven points clear of the drop-zone and Barcelona hope Raphinha's valuation reduces if they are demoted.
Sky Sports News reported their interest in signing two free agents, Cesar Azpilicueta and Andreas Christensen, who are both set to be free agents in the summer.
Barcelona have already agreed a pre-contract with a player from the Ivory Coast, and have recently registered their interest in a player from the other side of the world.
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The contract disputes between Barcelona and Ronald Araujo and Gavi are said to be being watched by the premier league clubs.
Araujo is currently one of the lowest-paid players in the squad, despite being the first-choice centre-back this season.
Sky Sports News has been told by sources in Spain that Barcelona have made a final offer of triple his current B-team-level salary.
With just over two years left on his youth terms, the 17-year-old sensation is in disagreement over his first pro-deal at the club.
The player feels that he should be on par with Spain internationals, since he has become a regular in the first team since making his debut last October.
The situation of Gavi is said to be closely monitored by big clubs across Europe, including from the premier league, despite reports in Spain that they are interested.
Barcelona vice-president Yuste said this week that they were working to keep the two players at the club. I am positive. The players are happy.