Guardiola's current contract with the Blaugrana expires at the end of the season and he has yet to give any indication as to whether he will sign one of his customary one-year extensions.
Consequently, the Catalan club's supporters are becomingly increasingly agitated but former Barca coach Rexach insists that there is no need for concern.
"I think this [the extension] is coming soon," the 65-year-old Spaniard is quoted as saying by AS. "This month it should be cleared up with relative ease.
"I think what Pep is doing is analysing the situation. He likes to analyse and have everything under control and that's fine.
"But there comes a time when things cannot go on any longer and I think he realises that now Barca have the jitters at all levels, so I think the decision will be taken quite quickly."
Guardiola has led Barcelona to 13 titles since taking charge of the club in 2008.
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