Iain Henderson insisted he "only ever had eyes for Ireland" after talks over a new two-year deal had dragged on into the 2021 Guinness Six Nations.
The 29-year-old second row has signed a two-year extension to his Irish Rugby Football Union contract and will remain at Ulster until July 31, 2023.
Henderson will have to agree new terms to play at the 2023 World Cup in France that autumn.
But the 2017 British and Irish Lions tourist says he is determined to do that and is just relieved his future has been resolved ahead of Ireland's Six Nations trip to Italy, with contract negotiations having been delayed by the impact of Covid-19.
"It's not fitting to call it drawn out, but it's been a long process and I'm delighted to get to the end of it," Henderson said ahead of Saturday's clash in Rome.
"The initial period was probably more stressful speaking in terms of the wider group.
"The contract negotiations were slightly later than maybe we would have initially anticipated, or where would be in usual years. Anyone in any profession would find that stressful.
"When they got underway, the discussions my agent had with David Nucifora (IRFU performance director) and other members of his team weren't painful at all.
"They were understanding and both sides of the table knew where we had to get to.
"It didn't take as long as I thought it would, but I've only ever had eyes for Ireland. Few players would try and play clubs off against each other.
"You wouldn't necessarily get that far down a line for clubs to be making huge cash offers or any cash offer before showing any real commitment.
"A lot of factors have made negotiations different."
Some members of Ireland's squad have yet to sort out their own futures with the Six Nations about to reach its halfway point.
And Henderson, who captained Ireland against France two weeks ago in the absence of the injured Johnny Sexton, admitted the squad's leadership group had to take that into account.
He said: "You've got to look out for each other and make sure everyone's fine with external stresses, be it contracts, family or college.
"You always have to be mindful of your team-mates, to have that extra eye outside the rugby circle.
"Because ultimately that will impact rugby performance, be it training, matches or sleep before a game.
"So being able to spot guys when maybe they're struggling a wee bit or not themselves, that's key, and Andy Farrell (head coach) is good at picking up on that and checking in on guys."
Ireland are seeking to kick-start their Six Nations campaign in Rome after losing their opening two Six Nations matches for the first time.
Farrell's side suffered narrow defeats to Wales and France, but Henderson has hailed the work of forwards coach Paul O'Connell and scrum chief John Fogarty.
He said: "Paulie hasn't come in and tried to reinvent it, he hasn't tried to take everything away.
"What he has done is let us continue what we were doing and added small tweaks to make us better session by session.
"Fogs has brought insight into the scrum. He's brought a whole new dimension and really encapsulated the eight as one, as he likes to put it, as we build for the weekend."