Fiala, like everyone else at the ceremony, was wearing a respirator when he signed the official document in front of Zeman, who was sitting inside the box which was constructed especially for the occasion.
Soon after the results were announced, the two coalitions signed a memorandum to form a government to unseat the current populist Prime Minister Andrej Babis.
Just a day after the election, the 77-year-old Zeman was rushed to hospital where he spent several weeks in intensive care for liver and other serious health problems.
One of the president’s main constitutional roles is to select the next prime minister to form a government, so Zeman’s hospitalization has left the country in a political deadlock.
Zeman was released from the hospital after 46 days on Thursday morning only to be sent back later in the evening after testing positive for Covid-19.
He was released again on Saturday, after showing no Covid symptoms, but with the requirement that he remains in quarantine.
During the ceremony, Zeman and Fiala spoke to each other using microphones. Zeman said he will next meet with Fiala’s prospective cabinet members individually, adding he wants to complete the process by December 13.
Until then, the new government is formed and secures a vote of confidence in the lower house of the Czech Parliament, Babis and his government remains in power.