Teenager Mark O'Hara has signed a two-year extension with Kilmarnock.
Relegated Hull have released longest serving players Paul McShane and Liam Rosenior as they reshape their squad.
The Seasiders have been led by former Scotland captain Barry Ferguson on a caretaker basis since Paul Ince was sacked in January.
But Bloomfield Road chairman chairman Karl Oyston wants McNamara to take charge permanently.
However, United released a statement which said: "Dundee United confirms it has denied Blackpool FC permission to speak to manager Jackie McNamara.
"The manager has been kept aware of the situation and declared that he is fully committed to the Club and very happy to remain at Dundee United for the foreseeable future.
"The Club will make no further comment on this matter."
Former Celtic defender McNamara replaced Peter Houston at Tannadice 18 months ago after quitting his first managerial post at Partick Thistle.
Since then, he has won plaudits for encouraging youngsters such as Ryan Gauld, Stuart Armstrong and Andrew Robertson to flourish.
A week on Saturday he will bid to win his first trophy as a boss when the Terrors take on St Johnstone in the William Hill Scottish Cup final at Celtic Park.
McNamara added: "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 over the last 18 months or so.
"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."
Meanwhile, United defender Mark Wilson reckons team-mate Nadir Ciftci was snubbed for the Scottish Premiership's young player of the year award - because he looks too old.
The 22-year-old Turk has enjoyed a sensational first season at Tannadice, netting 17 goals since signing for McNamara's team on a free transfer from Dutch outfit NAC Breda.
And he struck the crucial third goal against Rangers in the Scottish Cup last-four clash at Ibrox to book the Terrors a May 17 date with St Johnstone.
But while another United youngster, Andy Robertson, was named the best youngster in the top flight by PFA Scotland, Ciftci was not even nominated for the award.
And Wilson - whose side round off their league campaign when they face Celtic in Glasgow on Sunday - believes that is only because of his mature appearance.
He told Press Association Sport: "I was surprised Nadir wasn't nominated for young player of the year. I think most people look at him and think he has got one of those dodgy passports.
"He might have one because he looks about 30 but he's only 22.
"However, the skill and flair he possesses means he has been a real find for our team.
"The system we play, you need someone in the striker's position who can link things up, keep the ball moving and create things.
"But not only has he done all that, he's scored goals, important goals, too.
"He's young but I don't think he's been looked upon as a 22-year-old, which is strange. I can see where people are coming from because even in training, we forget he is young.
"We give him a hard time sometimes when he doesn't work as hard as he should be. But he is learning all the time."
Sunday's Parkhead clash will give United a sneak peek at the cup final venue before they face Saints
While the fourth-placed Arabs can no longer catch Motherwell in third, Wilson insists their final league game is a useful warm-up ahead of their clash with Tommy Wright's Perth men.
"There's a wee sense of anti-climax ahead of the Celtic game because we don't have much left to play for in the league," he admitted.
"But at the same time we are playing at Celtic Park the week before the cup final. For the manager he is going to be looking at his team and it is a good chance for us to go out there and familiarise ourselves with the pitch and the surroundings.
"So it is good prep for next Sunday."