United Nations chief Antonio Guterres on Friday urged Chad and Benin to respect civil rights and free speech as the two African nations hold elections this weekend.
Both countries have seen a succession of coups and rebellions since winning independence in 1960, and have been mired more recently in political crises sparked by disputed polls and opposition leaders being detained or sidelined.
In the latest violence Benin troops shot dead two protesters on Thursday as they cleared a blockade in the central city of Save, while activists accuse security forces in Chad of brutally stifling dissent by banning demonstrations, beating up activists and carrying out arbitrary arrests.
In Chad, where Sunday's vote appears set to hand 30-year leader Idriss Deby Itno a sixth term after his most prominent rivals were sidelined, Guterres stressed "the need to respect civil and political rights, including the rights to freedom of assembly and expression."
Guterres said in a statement that he hoped all parties involved in the process would "work towards a peaceful and credible electoral process."
The secretary-general "urges all stakeholders to resolve any disputes that may arise from the electoral process through dialogue and legal channels," the UN statement said.
Guterres issued a similar appeal to the various parties in Benin, which also holds its elections on Sunday.
"The secretary-general calls on all national stakeholders to ensure that the poll is conducted in a transparent, credible and peaceful manner," the UN said in a statement.
He said the organization stood ready to help the "country's efforts to consolidate democratic gains and social cohesion."
Benin's President Patrice Talon promised earlier Friday a "KO" first-round victory in an election that opponents say is already rigged after his main rivals were disqualified from running.