The Czech Republic, along with Germany, Poland and Austria, introduced the controls in September and October as the numbers of migrants crossing into richer western European countries grew.
The Czech controls were due to expire at midnight on Wednesday before the extension was approved at a government meeting.
"We are reacting to situation in neighbouring countries that are also extending (checks)," Rakusan said.
He said police checked more than 680,000 people and denied entry to more than 1,120 since October.
Slovakia has also put in temporary controls on its border with Hungary, but its interior minister has said they would be dropped after Jan. 22, according to Slovak media reports on Wednesday.
Slovakia experienced a several-fold increase in illegal migration in 2023 as migrants, mostly young men from the Middle East and Afghanistan, transited through the country after entering the European Union via Hungary and heading to the west, mostly to Germany.
(Reporting by Jan Lopatka and Jason Hovet; Editing by Alex Richardson)
