Liberia's leader President George Weah is being put to the test on Tuesday when a referendum will open asking whether to shorten presidential terms and whether to lift a ban on dual nationality.

Weah, a former footballing icon, wants to cut the length of terms for presidents and lower-house lawmakers from six to five years and from nine to seven for senators.

"Distinguished partisans, ladies and gentlemen; I want you to say yes to the referendum because it is in your interest," he said.

But some members of the opposition say Weah, who was elected in 2018, will aim to extend his stay in office because the first six years would then be under a different constitutional arrangement.

Reducing term limits is a relative novelty for the region, where ageing presidents have followed a pattern of clinging to office using constitutional changes.

In Guinea, for example, 82-year-old President Alpha Conde won a controversial third term in October after pushing through a new constitution that allowed him to bypass a two-term limit.

The same month, Ivorian President Alassane Ouattara, 78, was elected for an equally contentious third term, after having revised the country's constitution.

But voters are undecided.

"You know when it comes to the referendum, I don’t have (an) understanding on it yet. So for the referendum, I won’t really vote on it," said Amelia Johnson.

Another question being put to voters will be whether to scrap a ban on dual nationality.

It's a divisive issue in the poor West African country. Some hope it could lead to an economic boom but others say wealthy diaspora members could wield too much influence.

"Well really I feel that the referendum is not timely and I feel that this should not have been conducted during this time around because there were not much publicity carryout on the referendum," said Thomas G.