League of Ireland champions Dundalk and the country's three Europa League representatives will return to action on the European stage in August.
The Lilywhites will play in the first qualifying round of the Champions League on 18/19 August while league runners-up and FAI Cup winners Shamrock Rovers, Bohemians and Derry City will start in the first round of the Europa League qualifiers on 27 August.
The qualifying rounds will be one-off ties rather than the usual two legs, as UEFA makes space to conclude the 2019/20 season interrupted by the coronavirus pandemic, though the Champions League play-off round remains a two-legged affair.
The first qualifying round draws will be made a week before the games, following the preliminary round fixtures.
The Irish quartet returned to training last week ahead of a possible mini-tournament next month, while they and the rest of the country's clubs remain in discussions with the FAI over how to resume the domestic season, which was halted in March.
Women's National League champions, Peamount United, will begin their European campaign in the UEFA Women's Champions League qualifying round mini-tournaments, played between 7 and 13 October. The draw for the qualifying groups will take place in the first week of September.
UEFA has also confirmed that the culmination of this year's Champions League will be played out in Lisbon.
The eight teams remaining in the competition will take part in a straight knockout tournament between 12 and 23 August at the stadiums of Benfica and Sporting Lisbon.
Paris St Germain, Atalanta, Atletico Madrid and RB Leipzig are the four clubs who have already guaranteed their respective places in the last eight.
The four remaining last-16 second leg matches - Manchester City v Real Madrid, Bayern Munich v Chelsea, Juventus v Olympique Lyonnais and Barcelona v Napoli - will take place on 7 and 8 August.
UEFA is yet to determine whether those matches will take place at the respective host stadiums or in Portugal but a decision will be made before 10 July when the situation regarding international travel in the countries concerned has become clearer.
All remaining matches in the Women's Champions League will be played as a knock-out tournament in Bilbao and San Sebastian between 21 and 30 August.
In addition, the culmination of this season's Europa League from the last-eight onwards will take place as a knock-out tournament across four venues in Germany - Cologne, Duisburg, Düsseldorf and Gelsenkirchen - between 10 and 21 August, with the final taking place in Cologne.
UEFA president Aleksander Ceferin said UEFA would decide by mid-July whether fans could be present at the respective Champions League and Europa League tournaments.
He said: "If I would answer today, we don't think we could have spectators at the Champions League or Europa League finals, but things are changing rapidly.
"We will assess the situation at the beginning of July and we will see what the situation will be. It would be incompetent from us if we were to decide in advance about the situation."
He also ruled out the possibility of the knock-out format being used in future seasons, even if it proves to be a hit.
"It couldn't be a suggestion for the future," he said. "It will be very interesting I'm sure, but we are forced to do it because the leagues need time to finish in July, so we have to do everything in August. That's due to this Covid crisis and it's not an idea for the future."
Clubs will be allowed to register three new players for the remainder of the 2019/20 season, provided such players had already joined the club by February, but they would have to replace existing players as the squad maximum remains at 25.
The 2020 Champions League final had been due to be played in Istanbul, but instead the Turkish city will host the showpiece match in 2021.
That means all previous hosting awards will be pushed back a year, so that St Petersburg holds the final in 2022, Munich in 2023 and Wembley in 2024.
The Polish city of Gdansk had been due to stage the Europa League final, but will now do so in 2021 instead.
UEFA Champions League 2019/20
Last-16 second legs: 7-8 August
Quarter-finals: 12, 13, 14, 15 August
Semi-finals: 18, 19 August
Final: 23 August
UEFA Europa League 2019/20
Quarter-finals: 10, 11, 12, 13 August
Semi-finals: 16, 17 August
Final: 21 August
UEFA Champions League 2020/21
Preliminary round: 8 and 11 August
First qualifying round: 18/19 August
Second qualifying round: 25/26 August
Third qualifying round: 15/16 September
Play-offs: 22/23 and 29/30 September
Group stage: 20/21 and 27/28 October, 3/4 and 24/25 November, 1/2 and 8/9 December
UEFA Europa League 2020/21
Preliminary round: 20 August
First qualifying round: 27 August
Second qualifying round: 17 September
Third qualifying round: 24 September
Play-offs: 1 October
Group stage: 22 and 29 October, 5 and 26 November, 3 and 10 December
UEFA Women's Champions League 2020/21
Qualifying round mini-tournament: 7 and 13 October