The new constitution proposed by Guinea's President Alpha Conde, which will be submitted to a referendum on Sunday, has fuelled fears among the opposition that he is seeking a third term.
Several other African leaders have also sought to hang on to power through changes to the constitution.
Here are some examples.
In Comoros, in 2018, a constitutional referendum allowed President Azali Assoumani to be elected a second time in 2019, at fraud-tainted polls, according to international observers.
In Rwanda, a constitutional reform voted by referendum in 2015 allowed President Paul Kagame to secure a new term in 2017 and to potentially rule until 2034.
The same year the Republic of Congo (Brazzaville) voted by a landslide on constitutional changes allowing veteran ruler Denis Sassou Nguesso to run for a third term. He was re-elected in 2016.
Burundi was plunged into a bloody political crisis in which at least 1,200 were killed, after Pierre Nkurunziza won a highly controversial third term in 2015. He stunned observers by not standing for re-election in 2020, despite a May 2018 referendum allowing him to do so.
In Zimbabwe, a new constitution adopted in 2013 let Robert Mugabe stand in another election, which he won. He was forced to step down in 2017, after 37 years in power. He died in September 2019.
In Djibouti, in 2010, parliament approved a constitutional amendment allowing President Ismael Omar Guelleh, in power since 1999, to run for a third term. He was re-elected in 2011 and 2016.
In Algeria, in 2008, parliament revised the constitution to quash the limit on the number of presidential terms to two. President Abdelaziz Bouteflika, in power since 1999, was then re-elected in 2009 and 2014. He was forced to resign in April 2019 following massive popular protests.
In Cameroon, in 2008, parliament revised the constitution, scrapping the limit on the number of presidential terms. Paul Biya, who had been in power since 1982, was elected to a seventh term in October 2018.
In Uganda, also in 2005, a constitutional reform scrapped limits on presidential terms. In 2019, the Supreme Court confirmed the scrapping of the age limit for the presidency, allowing Yoweri Museveni, in power since 1986, to stand for re-election in 2021.
Chad's Idriss Deby Itno has been in power since 1990 thanks to a constitutional revision in 2005 that was adopted after a disputed referendum.
In Togo in 2002 a constitutional amendment allowing the president to seek reelection without limit paved the way for Gnassingbe Eyadema, in power since 1967, to win another term.
When he died in 2005, his son Faure Gnassingbe took over and has since won four contested elections.
In Burkina Faso, the announcement in 2014 that long-serving president Blaise Compaore sought to extend his rule beyond 30 years brought hundreds of thousands of protesters onto the streets. Compaore was forced to stand down.
In Zambia, Frederick Chiluba, was forced in 2001 to bow to popular pressure after trying to change the constitution in order to get a third term. In Malawi, parliament in 2002 blocked Bakili Muluzi from seeking a third mandate in 2004.