The message came from Mondlane himself via the social media platform Facebook on Sunday.
If they kill my brothers, they kill my brothers, then I'll be there, said Mondlane and confirmed that he is traveling to the capital Maputo on Thursday.
Regime-critical protests following the disputed election held in October are shaking the East African country, and several hundred demonstrators are reported to have lost their lives in clashes with security forces.
The main reason for the discontent is that the ruling party Frelimo's presidential candidate Daniel Chapo has been declared the winner of the presidential election, and Chapo will be sworn in as president in mid-January.
Opposition groups claim that electoral fraud has occurred and several election observers report irregularities in the election, which the regime denies.
Frelimo has ruled the country since independence from the colonial power Portugal in 1975.
