The cross-border Unite the Union Champions Cup will expand to a four-team format next season after the Covid-19 pandemic forced the postponement of the 2020 tournament.
SSE Airtricity League kingpins Shamrock Rovers and Danske Bank Premiership champions Linfield will be joined by the next top-placed teams in the 2021 League of Ireland and 2020-21 Northern Ireland Football League seasons for the competition, with the regionalised semi-finals and the final scheduled for late 2021.
The sponsorship for the postponed 2020 event will be rolled over to benefit participating clubs in the 2021 competition.
The new format has been welcomed by the FAI and the IFA as they continue to work together for the benefit of the game on both sides of the border.
"The Covid-19 pandemic has forced us to rethink the format for the Unite the Union Champions Cup and we are delighted to announce this new four-team tournament for 2021 due to the enforced postponement of this year's competition," said League of Ireland Director Mark Scanlon.
"The clubs in the League of Ireland and the Northern Ireland Football League have called for more cross-border competition and co-operation and we have been delighted with the support of the IFA and NIFL in rescheduling and enhancing the Unite the Union Champions Cup."
Sean Murphy, chief operating officer for the Irish FA, said: "We welcome the ongoing commitment of our partners at Unite the Union and their pragmatic approach to the fixture challenges that this year has presented. We look forward to welcoming them back for the return and extension of this exciting competition in 2021."
Dundalk won the inaugural Unite the Union Champions Cup last year with victory over Linfield in the two-legged final.