Argentina play Ecuador in their final qualifying match on Wednesday morning, where they will need all three points to give themselves a chance of going to Russian Federation next year. Wales need just a draw to be guaranteed to finish second, whereas the Irish must win to reach the play-offs and keep their World Cup dream alive.
Brazilian, Mexican, Argentinian, US, German, Colombian, Chinese, Israeli and English fans all rank in the top 10, with more and more worldwide fans expected to apply for tickets as teams continue to qualify.
"With the qualifiers for the 2018 FIFA World Cup Russia™ approaching their end and more and more teams securing their places at next year's finals, the first ticket sales period for FIFA's flagship tournament is soon to conclude", the statement said.
Iran, South Korea, Japan and Saudi Arabia were the first four Asian nations to qualify.
Below is how the pots are looking for the draw, which takes place on Friday. These teams were also the four runners-up who had the best record in group qualifying.
Northern Ireland and Republic of Ireland can not face each other as both countries will be unseeded, joining Sweden and Greece - who secured a play-off place with a 4-0 win over Gibraltar on Tuesday - in the same pot. They advanced from the group stage both times, but they could expect a kinder draw this time. The Super Eagles direct their team with 13 points after five games and secured qualification with one game to spare, while Zambia, 2017 AFCON champions Cameroon and Algeria will miss out.
Australia and Syria, who finished their respective groups in third place, will face each other. The home team in the first leg is also drawn, so the seeded team does not automatically play at home in the second leg. In the past tournaments, Mexico were grouped with fellow CONCACAF nations and Asia teams (as well as New Zealand in 2010). The final spot will be determined between Panama, United States and Honduras.
Who has already qualified for the World Cup?