Antigua is seeking permission to run a website that sells music, movies and software - but ignores copyright law.
The Caribbean island is due to appear before the World Trade Organization (WTO) on 28 January seeking permission to run the site.
The decision to set up the site is the end point of a long-running dispute with the US over gambling.
The US has objected to Antigua's plan saying it amounted to official "piracy" of intellectual property.
Officials from Antigua will make their plea before the WTO's dispute settlement body on Monday to get "final authorisation" to set up the site, Mark Mendel, a lawyer representing the island nation told the BBC.
Antigua went to the WTO after the US moved to stop American citizens using gambling services, including web-based betting shops and casinos, run from the Caribbean country. Antigua claims that action deprived it of billions of dollars in revenue.
The WTO agreed with Antigua and dismissed a US appeal against its ruling. However, because the US took no action to lift the controls on cross-border gambling Antigua filed an application to recoup its lost cash by other means.
It sought permission to sell movies, music, games and software via a store that would be able to ignore global agreements on copyright and trademark controls, reports filesharing news site TorrentFreak. It wanted to be able to sell up to $3.4bn (£2.15bn) of those goods before having to make copyright payments.
The WTO rejected that figure, but said Antigua could sell $21m (£13.2m) annually via the store before it had to consider paying copyright fees. The US is believed to have offered to pay Antigua $500,000 annually as compensation for the lost revenue.
The US has also written to the WTO criticising Antigua's plans. In a letter to the WTO, excerpted on the Caribbean 360 news website, it said the plan amounted to "government-authorised piracy".
It also warned that if Antigua did go ahead with its plan "it would only serve to postpone the final resolution of this matter, to the detriment of Antigua's own interests".
Mr Mendel added that just because Antigua had permission to run the site did not mean it would go on to set it up.
"When or exactly how it will do so is within the government's discretion and will be considered and taken or not in due course," he said.