The Belarus intelligence service - the KGB - says it has uncovered a US spy ring, amid renewed tensions between the US and the ex-Soviet republic.
US diplomats have urged Belarus to free political prisoners
A KGB official confirmed a report on Belarus state TV which said a US diplomat had recruited 10 Belarusians.
The US embassy in Minsk denied the allegation, first aired at the weekend.
The US announced on Monday that it was cutting its diplomatic staff in Minsk from 35 to 17, in line with a request from Belarus.
Both countries recalled their ambassadors earlier this month. The move followed Washington's imposition of sanctions on the Belarusian state oil company Belneftekhim.
Belarus announced it was withdrawing its ambassador to Washington and asked the US to follow suit.
Minsk has accused the US of violating agreements aimed at normalising diplomatic relations.
As well as sanctions on individual companies, both the US and the EU have imposed travel bans on Belarusian President Alexander Lukashenko and some of his top officials.
They have demanded that President Lukashenko frees political prisoners and allows more democratic freedom, before normal relations can be restored.