All the League of Ireland players and staff who underwent testing for Covid-19 on Monday have returned negative results.
Dundalk, Shamrock Rovers, Derry City and Bohemians were tested as they prepare for a return to training on 8 June.
The FAI announced this evening that nobody has tested positive for the virus, clearing the way for a safe return for all football in this country.
FAI Medical Director Dr Alan Byrne received the results today. All those tested have been informed of their negative result.
The players and staff from the four clubs will be tested again next Monday ahead of a planned return to training on 8 June, as part of the pilot programme to ensure a safe return for football at all levels.
"This is most welcome news and a very positive step as we work with Government, their agencies and all stakeholders in the game towards a safer return for all of Irish football," said FAI Interim Deputy CEO Niall Quinn.
"These negative results are an early boost for everyone in the game but it is only the start.
"We have to remain vigilant and we again urge all affiliates - clubs, players, supporters and parents - to abide by the Government and HSE guidelines."
A pilot tournament is planned for July involving Dundalk, the Hoops, Derry and Bohs - the four clubs who have qualified for European football.
The FAI are set to present clubs with a financial proposal next month which is also key to securing the resumption of the 2020 season.