Former Arsenal captain Vieira has emerged as a candidate to replace Unai Emery, who was sacked by the struggling Premier League club last week.
But Vieira – a three-time Premier League champion with Arsenal – played down the speculation ahead of Nice's Ligue 1 clash against Metz on Saturday.
"I don't have any comments," Vieira told reporters. "Sincerely. It's a question I don't have to answer.
"Sincerely, I am 100 per cent focused on what I have to do here. And I think I have a lot of things to do here. And I don't want to spread myself over anything.
"I am 300 per cent focused on how I can try to find solutions to be more constant, to win more games. Find solutions to get the best of my players. I want to put my energy and my concentration only on that."
Nice are 14th in Ligue 1 this season, five points above the relegation play-off spot following just one win in four matches.
Vieira said: "I communicate a lot with Julien [Fournier, football director], with the president [Jean-Pierre Rivere] and with Mr. Ratcliffe [owner]. I have their support.
"We talk, we discuss. The goal is to find solutions, to improve. I have never felt the slightest doubt about their attitude to my work. It's reassuring."