  Given an inclusion $A\to L$ of Lie algebroids sharing the same base manifold
$M$, i.e. a Lie pair, we prove that the space $\Gamma(\Lambda^\bullet
A^\vee)\otimes_{C^\infty(M)} \frac{U(L)}{U(L)\cdot\Gamma(A)}$ admits a natural
$A_\infty$ algebra structure. This $A_\infty$ algebra structure is inherited,
by homotopy transfer, from the universal enveloping algebra of the differential
graded Lie algebroid arising as the pullback of the Lie algebroid $L\to M$
through the canonical surjective submersion $A[1]\to M$.
