The 32 teams competing for the biggest club prize in football will learn their opponents at a draw on Thursday. The event at the Grimaldi Forum in Monaco is due to take place at 4.45pm BST.
The teams will be drawn into eight groups of four teams.
The four teams comprising each group will come from four pots dictated on a seeding basis. No team from the same country may face each other at this stage of the competition.
England has three representatives in the draw in Manchester City, Liverpool and Chelsea. Should Arsenal overcome Besiktas on Wednesday night they will also be involved. There are no sides from Scotland after Celtic lost to Maribor on Tuesday night.
Should Arsenal qualify, they will join Chelsea among the top seeds in Pot 1. Manchester City are in Pot 2 whilst Liverpool are in Pot 3.
The seeding is based on a club's Uefa coefficient.
Pot 1: Real Madrid, Barcelona, Bayern Munich, Chelsea, Benfica, Atletico Madrid, Arsenal, Porto
Pot 2: Schalke 04, Borussia Dortmund, Juventus, Paris Saint-Germain, Shakhtar Donetsk, Basel,Zenit Saint Petersburg, Manchester City
Pot 3: Bayer Leverkusen, Olympiacos, CSKA Moscow, Ajax, Liverpool, Sporting CP, Galatasaray, Athletic Bilbao
Pot 4: Anderlecht, Roma, APOEL, BATE Borisov, Ludogorets Razgrad, Maribor, Monaco, Malmo FFReuse content