Hundreds of people have tried to force their way into the North African Spanish enclave of Ceuta in recent days, while Italy is grappling with a new wave of arrivals crossing the central Mediterranean aboard small boats.
"Europe shouldn't be a sort of useful idiot in the battle against the virus," the French presidential adviser told reporters ahead of a virtual EU summit on Thursday.
The regulation is aimed at making vaccine trade reciprocal and proportional so that other vaccine-making countries sell to Europe and the EU does not export much more than it imports, one EU official said.
EU diplomats said that leaders last week urged Michel to cancel the in-person meeting, though he had hoped to tighten sanitary measures to avoid reverting again to a videoconference.
Leaders were looking to salvage the EU's 1.8-trillion-euro ($2.1-trillion) budget and coronavirus recovery package, seen as vital for the continent's battered economies, after it was blocked by Hungary and Poland over provisions linking it to the respect for rule of law.
Rau's comments come after Poland's Prime Minister Mateusz Morawiecki and ruling party leader Jaroslaw Kaczynski met with Hungarian Prime Minister Viktor Orban in Warsaw on Tuesday evening.