The tiny oil-rich central African nation of Equatorial Guinea is carrying on plans to erect a wall along its 183km-long border with Cameroon.

The plans have sparked controversy with Cameroon authorities because of concerns about encroachment into Cameroon’s territory. Equato-Guinean officials are said to have already erected milestones to demarcate the line along which the border wall will be constructed.

The move, similar of US president Donald Trump’s pledge to build the controversial US-Mexico border wall, has angered Cameroon’s government. It dispatched its army chief of staff at the end of July to the border town of Kye-Ossi for a situation report and stationed elite forces along the border.

There has been a history of border friction between Cameroon and Equatorial Guinea. Tensions have been rising between the central African neighbors since Equatorial Guinea discovered oil in the 1990s. The smaller country has often blamed Cameroon for allowing illegal migrants from West and Central Africa, especially Nigeria and Cameroon, to pass through en route to Equatorial Guinea in search of economic opportunity. Eq Guinea officials seems to fear an influx of foreigners will weaken efforts to provide jobs to its citizens, majority of whom still live in poverty.

REUTERS/Sylvain Andzongo Signs are seen on the border with Equatorial Guinea and Gabon in Kye-Ossi, Cameroon

Equatorial Guinea has also been especially keen on border security following the arrest of 30 heavily armed men from Chad, Sudan and CAR along the border in what it saw as an “attempted coup d’état by mercenaries.” The last time Equatorial Guinea closed its border with Cameroon because of the reported coup attempt in December 2017, it was only reopened in January 2019.

Over the last decade, Equatorial Guinea has become one of Africa’s wealthiest countries as the fourth largest oil producing country in Sub Saharan Africa but with a tiny population of just over 1 million. World Bank data shows it has a gross national income per capita of $7,050 compared to neighbors like Cameroon of $1,440 or even Nigeria’s of $1,960. At various points in the last 15 years, depending on global oil prices, Equatorial Guinea has been informally designated as Africa’s wealthiest country.

On paper Equatorial Guinea could be seen as a booming country because of its abundant petroleum resources and huge investments in infrastructure development, thus attracting economic migrants. However, in terms of development indices, it is not much better than Cameroon or other African countries because of political corruption and the high-handedness of the Obiang family which has ruled the country since independence in 1968. It is ranked 141st out of 189 countries in the UN Human Development Index of 2018.

President Teodoro Obiang Nguema Mbasogo, Africa’s longest serving ruler, has been in power since August 1979 after ousting his uncle Francisco Macías Nguema in a coup. Over his 40-year rule, he and has family have been accused of mismanaging the country’s wealth while also scoring low on both human rights and press freedom rankings.

President Obiang Nguema as well as his son and likely successor, Teodoro Nguema Obiang Mangue, who is vice president, have both been mired in allegations of corruption and misappropriated public funds.

In 2017, a French court slammed Teodoro Nguema Obiang Mangue a three-year suspended sentence after finding him guilty of embezzling $175 million of public funds to buy real estate, luxury cars and other assets. The playboy son of president Obiang Nguema has also been under investigation by Swiss authorities for financial crimes.

Besides causing a diplomatic roar, critics of president Obiang’s action believe it contradicts the spirit of the African Continental Free Trade Area and other similar regional agreements for the free movement of persons and goods to which the country has committed to.

The move by Equatorial Guinea is counterproductive whatever the reasons advanced by its authorities and goes a long way to compromise continental efforts, says Bama Etienne Cham, senior trade policy advisor at the Cameroon National Shippers Councils.

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