The Championship club are still looking for a permanent successor to Paul Ince, who left Bloomfield Road in October.
And the search goes on after United refused Blackpool permission to speak to their manager, while McNamara has made it clear he wants to extend his 18-month spell at Tannadice.
He said: "While flattered at the interest shown, I am very happy at Dundee United and wish to continue the job and build upon the foundations laid down.
"I view the approach as a positive endorsement of all the hard work undertaken by everyone at the club in that period and have no plans to leave.
"All of my focus is on the forthcoming William Hill Scottish Cup final and preparations for the new season ahead."
Blackpool chairman Karl Oyston said this week he wants to make an appointment within 10 days, although he was unsure on the future of caretaker boss Barry Ferguson.
"I've still not spoken to Barry," Oyston said. "I've not had the opportunity. I need to speak to him to see where he stands.
"He seems to have made it clear in interviews he's off to have an operation and maybe sees a future playing.
"But that needs to be resolved and we need to do it quickly."