Republic of Ireland's 5-1 World Cup playoff defeat to Denmark has seen them drop six places to 32nd in the Federation Internationale de Football Association world rankings.
Iran remains Asia's top-ranked team as it moved up to 32 in the rankings, an improvement of two places from October.
Australia - thanks to their FIFA World Cup 2018 Play-off wins over Syria and Honduras - also saw an improvement as the Asian champions jumped to 39th from 43rd spot previously.
Wales, who Martin O'Neill's team beat to a World Cup playoff spot, drop five places to 19th.
Eagles drop in Federation Internationale de Football Association rankings despite improved form
There was no change in the top five on the global list as Germany held firm at the top‚ followed by Brazil‚ Portugal‚ Argentina and Belgium. Switzerland moved into the top ten bracket and are now eight while France and Chile complete the top ten in ninth and 10th respectively.
"We are looking at countries that are above us in the ranking and countries that are in the top 10 of world football ranking and countries that are in the World Cup as well".
Iran, Japan, Saudi Arabia, Korea Republic and Australia will be Asia's representatives at the FIFA World Cup 2018 Russian Federation.
Seychelles, who will host the Eagles on matchday two in Group E of the 2019 Africa Cup of Nations qualifiers next year, dropped one place from their 188th position last month to 189th.