Hana Humpalova and Antonie Chrastecka were on the road from Iran to Quetta, the capital of Pakistan's southwestern Baluchistan province, when they were seized in March 2013.
They returned home last year in March and the government said their release was negotiated by a Turkish non-governmental humanitarian organization.
Zeman confirmed Wednesday information about the ransom first released in the latest edition of the weekly magazine Respekt. Zeman said during a visit to a western Czech region that 150 million koruna (USD 6.2 million) was paid, adding it was a tough decision.