The deadline for political parties, movements and independent candidates running in the autumn Senate and local elections expires at 4pm on Tuesday.
Local elections and elections to a third of the Senate are due to take place on October 5-6.
Voters will elect 27 new senators which may re-affirm or break the dominant position of the Social Democrats in the upper chamber.
The ANO party will be defending its victory in local elections four years ago, when it was the leading force in Prague and other big cities.
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