Harry Kalaba said "levels of corruption are swelling."
Zambia's Foreign Affairs minister Harry Kalaba resigned late Tuesday citing corruption in government.
In a post on his Facebook page, Mr Kalaba said he handed in his resignation letter for the “position I have cherished and held for over four years”.
“We cannot proceed to manage national affairs with cold indifference when the levels of corruption are swelling and being perpetrated by those who are expected to be the solution,” he said.
"It would appear that the poor Zambians have ceased to be the reason we are holding power. Materialism and the propensity for money has taken over and is arrogantly at the centre of many decisions being made today,” he added.
A day earlier, Mr Kalaba, in a post on the social media platform, denounced corruption and poor governance, ruffling some members of the ruling party who called for him to resign.
Mr Kalaba was first appointed to Cabinet in 2014 by the late president Michael Sata and continued in his position under President Edgar Lungu.
He becomes the third minister to leave office after President Lungu fired his National Development Planning minister Lucky Mulusa last week. Last November, the President fired Information minister Chisimba Kambwili.