The eight-times grand slam champion was named in Sunday's player draft for the new Asia-based event but said he had since learned the first match would clash with the November holiday.
"It's a good thing to take tennis to places in the world where they want to see it. There's no downside in doing that," American Agassi told Reuters ahead of his World Tennis Day showdown with former arch-rival Pete Sampras in London later on Monday.
"My agreement to do it was based on a few very specific conditions. Certainly economics played a little part in it but also time away played another part.
"I can't be away for more than four or five days so I set some limitations and had some dates in December.
"Now I read in an email that the dates are over Thanksgiving," said the 43-year-old Agassi who is married to former women's world number one Steffi Graf and has two children.
"That would be a non-starter for me. Six or seven days away is too much of a price to pay."
The draft for the IPTL set up by Indian doubles specialist Mahesh Bhupathi saw the four teams - Singapore, Dubai, Bangkok and Mumbai - bid for players. Organisers said a total of $24 million was spent.
Modelled on the successful Indian Premier League cricket competition, the IPTL would take advantage of an earlier finish to the ATP and WTA seasons and involve a five-set format made up of a men's singles, women's singles, men's doubles, mixed doubles and a past champions singles.
Fellow American Sampras also appeared slightly in the dark on Monday.
"It's happened in the last 24 hours," he told Reuters. "I've just been in talks with them and I'm excited to be a part of it. It's a big endeavour by the guys who are putting the whole thing together.
"It's not an easy thing to do though and we'll have to see how it all plays out in the next weeks. I'll get more details when I get home."
Sampras said he would never have entertained the idea of playing in the competition when he was at his peak.
"I didn't have a lot of time off so it would have been a tricky thing to commit to," explained the 42-year-old American.
"It's a long journey to Asia and I'm not sure how it would have played out for me. That was my time off."
The IPTL is scheduled to begin in Singapore on Nov. 28, the day after Thanksgiving, and a week after the Davis Cup final.
Andre Agassi was speaking ahead of his participation at the World Tennis Day in London. Andre Agassi plays Pete Sampras in an exhibition match while Lendl will face former adversary Pat Cash - watch LIVE on Monday on Eurosport from 7:30pm UK time.