The Scottish and Irish rugby unions have reached agreement with their Welsh counterparts over a future structure for the Celtic League.
Wales were expelled from the competition on May 31 after joining a new Anglo-Welsh Cup competition.
The Anglo-Welsh Cup was designed to replace the Powergen Cup in the English domestic calendar but its creation required Welsh clubs being free of Celtic League fixtures for five weekends of the season.
Scotland and Ireland objected but the Welsh Rugby Union insisted they remained fully committed to the Celtic League and agreement was reached at a summit meeting at Heathrow Airport on Friday.
A statement read: "As a consequence of a very positive and productive meeting in London today the Celtic League Association confirm that the three unions have reached agreement to accommodate the proposed Anglo-Welsh cup competition in the 2005-06 season."
The expulsion of the Welsh regions had left them facing the possibility of just nine guaranteed fixtures per term.
But the WRU believed a solution could be found by arranging fixtures in a certain way and having Welsh clubs play in midweek.
No details of the format of the competition have yet been given, although the Celtic League Association are planning to issue a further statement on Monday.