"We know his heart is in South Sudan," Samuel Abe, secretary general for the archdiocese of Juba said on Monday.
"My wish is if he comes he can be a voice for the voiceless."
Francis had planned to visit the country in October, but cancelled citing security concerns caused by the country's civil war.
He has donated 25 million euro to help feed the country's most vulnerable citizens ahead of the upcoming dry season.
The money was given to the United Nations' agricultural arm, to alleviate a period of "grave food insecurity and major displacement", said the Vatican.
