FIFA has confirmed the 2034 World Cup will be held in Saudi Arabia, while the 2030 World Cup will be co-hosted by Spain, Portugal and Morocco with the opening three matches in South America, according to Sky Sports.
Both bids were uncontested and were ratified at an online FIFA Congress on Wednesday, with the English, Scottish and Welsh Football Associations supporting the bids.
Saudi Arabia emerged last year as the sole bidder in a controversial process that saw FIFA combine the decisions on the 2030 and 2034 tournaments into a single vote, meaning delegates either supported or opposed both bids with no separate vote available.
FIFA Congress also ratified the centenary 2030 World Cup, which will be held across six countries in three continents with the opening three games taking place in Argentina, Paraguay and Uruguay.
But the decision to award Saudi Arabia hosting rights in 2034 is highly controversial, with critics arguing it is an effort to 'sportswash' the authoritarian regime's reputation.
The country will host football's most high-profile tournament for the first time and is the latest example of Saudi's growing influence on global sport.
It hosts Formula 1, boxing, golf and tennis, while the country's Public Investment Fund (PIF) has set up LIV Golf and purchased Premier League side Newcastle.
Saudi Arabia's bid was given the highest-ever score by FIFA's bid evaluation team and deemed only 'medium risk' on human rights. Amnesty International described FIFA's report as "an astonishing whitewash".
The 2034 World Cup in Saudi Arabia will also be the first time the expanded 48-team tournament is held in just one country, with the 2026 World Cup being held in the United States, Canada and Mexico.
Saudi Arabia was effectively handed the finals by an agreement reached at a FIFA Council meeting on October 4 last year.
Spain, Portugal and Morocco's 2030 bid had initially been up against a rival South American bid, but an arrangement was made for South America to instead stage the opening three matches of the centenary 2030 finals, with Spain, Portugal and Morocco hosting the rest.
That meant only countries from Asia or Oceania were eligible to host 2034 under FIFA's rotation system, with FIFA confirming interested nations from those continents had less than a month to put themselves forward.
Saudi Arabia duly did - on the same day the new arrangement was publicised - with Australia announcing on October 31 it would not stand as a rival.