CANBERRA, Australia—Foreign tourists won’t be welcomed back to Australia until at least next year, the prime minister said Tuesday as he outlined plans for lifting some of the toughest and longest COVID-19 travel restrictions imposed by any democracy. The country will instead prioritize the return of skilled migrants and students after it hits Prime Minister Scott Morrison’s benchmark for reopening its external borders: the full vaccination of 80 percent of the population aged 16 and older. It is expected to reach that point Tuesday. The news comes just days after Morrison announced plans to allow vaccinated citizens and permanent residents to fly overseas from November for the first time since March 2020. The severe travel restrictions, which have trapped most Australians at home and kept most foreigners out, have led to the lowest level of immigration since World War II. Australian universities, which rely heavily on fees paid by international …