Ban's aide also refuted an opposition lawmaker's claim that his brother's company was expelled from the UN Global Compact after engaging in mining activities that ran counter to the initiative's environmental principle. 

The initiative is a corporate sustainability movement that underscores universal principles on human rights, labor, environment and anti-corruption.

Ban's aide said that his brother has no relations to any illegitimate mining business.

Allegations involving Ban's relatives emerged amid his aggressive efforts to build grassroots support ahead of a presidential election this year. 

Though Ban has yet to officially declare his bid for the country's top elected office, he has repeatedly signaled his strong presidential ambitions, vowing to work for a change in politics -- in an apparent swipe at establishment politicians. (Yonhap)