The pair are both at the Eneco Tour this week, looking for a final chance to impress the national selectors, but Greipel isn't happy that the decision of who will race has been left so late.
"It's incomprehensible that the union has not made a choice," said Greipel, quoted in Het Nieuwsblad.
"I don't understand the union at all. I want to prepare as well as possible at the World Championship, but I'm not sure I will go. I cannot even plan my trip. "
He added: "For Marcel is that exactly the same. This is just a very awkward situation for both of us."
It seems unlikely that both Greipel and Kittel will be selected for the road race, given their shared interest in winning the race. Het Nieuwsblad suggests that John Degenkolb could be the backup sprinter should the protected rider come into trouble in the race.
German national team coach Jan Schaffrath is employed by Etixx-Quick Step during the season, presenting a conflict of interest. At Schaffrath's own request, the team selection decision has been handed to Andreas Klier, a sports director at Cannondale-Drapac.
When the names of the squad have been decided, it is then presented to a four-man board to finally sign it off. Germany has not had a road race world champion since Rudi Altig won at the Nurburgring in 1966.
Steve Cummings also recently admitted his frustration at the delay in selecting the Great Britain squad for the Championships.
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