The draw is due to take place at around midday BST on Friday, July 14.
The ties will take place on July 27 and Aug 3.
The seeded clubs will include Zenit St Petersburg, Athletic Bilbao, AC Milan, PSV Eindhoven, Bordeaux, Everton, Marseille and Freiburg.
There will be many either/or ties with the second qualifying round to be completed next week.
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