Ukrainian President Volodymyr Zelenskyy said the Russian truck drivers who transported what would become platforms for Ukraine's large-scale surprise drone attack on Russian warplanes a week ago did so unwittingly.

In the attack, drones used to conduct the attack were hidden in "mobile houses" that had retractable roofs, which were loaded on the trucks and then opened remotely to conduct the operation, a source told ABC News.

"They didn't know anything," Zelenskyy told Martha Raddatz in an exclusive interview.

Watch Martha Raddatz's full interview with Volodymyr Zelenskyy airing Sunday on "This Week with George Stephanopoulos."

"They just did their job," he said.

Zelenskyy said the drivers were unaware the mobile cottages and other containers they transported were clandestinely equipped with drones that would assault Russian airfields and damage billions of dollars of military hardware.

Ukraine has said it damaged over 40 Russian bombers in the attacks, amounting to about a third of Russia's strategic bomber fleet.

The Ukrainian president also told Raddatz that the nation's secret services "used only our weapon[s]" and did not deploy equipment originating in an ally's arsenal.

"I wanted very much to use only what we produce and to have the separation [be] very clear," Zelenskyy said.