Plans for a Test championship and one-day international league have been approved by the International Cricket Council.
Nine teams will play six series of Test matches over a two-year period - three at home and three away - culminating in a world Test championship final.
A 13-team ODI league, introduced from 2021, will now be used to qualify for the World Cup.
The ICC has also given the go-ahead for a trial of four-day Test matches.
"Throughout the discussions about the future of Test cricket it became clear that we must also consider alternatives and trial initiatives that may support the future viability of Test cricket," ICC chief executive David Richardson said.
Nine teams will play six series of Test matches over a two-year period - three at home and three away - culminating in a world Test championship final.
A 13-team ODI league, introduced from 2021, will now be used to qualify for the World Cup.
The ICC has also given the go-ahead for a trial of four-day Test matches.
"Throughout the discussions about the future of Test cricket it became clear that we must also consider alternatives and trial initiatives that may support the future viability of Test cricket," ICC chief executive David Richardson said.