Alonso previously affirmed that he was interested in an F1 return in 2021 when the new technical regulations were set to be introduced, however they have since been delayed due to the ongoing coronavirus pandemic.
Last week, the Spaniard stated that he knows what he will be doing in 2021 and was hoping that he could make his plans public soon.
Spanish reports have stated that Alonso is in talks with Renault over a return that would see him race alongside Esteban Ocon.
Should Alonso return to Renault, it would mark his third stint with the team, having originally competed for it from 2003 to 2006 and again in 2008 and 2009.
Spanish outlet AS states that a return for Nico Hulkenberg at Renault is not on the cards as such a move would come too soon after he was replaced at the team at the end of the 2020 season.
However, both drivers must achieve fourth or higher in this year's FIA Formula 2 championship in order to obtain a super licence needed to compete in F1.
Bahrain International Circuit - Winter testing