The news anchor is expected to leave her position as co-host of The Today Show later this year in order to avoid the early morning filming schedules and spend more time with her husband, who suffers from multiple sclerosis.
"NBC is doing everything they can to convince her to stay," a source told TV Guide, insisting that the network is dedicated to resolving the issue.
However, an NBC rep said in a statement: "The Today show anchors are currently under contract and firmly in place."
Viera - who replaced Katie Couric on Today in 2006 - opted to sign only a one-year contract extension last year rather than a longer arrangement.
She previously said that she feels "cheated" by her husband's illness as it affects every aspect of their relationship.
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