An internet curfew and social media blackout has sparked outrage and wreaked havoc on businesses in oil-rich Gabon, as citizens keenly await a pivotal ruling challenging President Ali Bongo's contested re-election.

"We are losing a lot of money," fumed Steeve Ndong, who oversees the website of a mobile telephone company.

"The figures of the page I look after are in the red. We are now down to 600 hits a day against between 6,000 and 10,000 normally," he said.

"It has lasted for 15 days," added Raoul, a doctor in the seaside capital Libreville, adding "(and) we speak of democracy."

Internet connections were partially restored on Thursday between six in the morning until 8 at night and then cut off later. Social media such as Twitter, Facebook and What'sApp remain blocked.

Gabon, which has been ruled by the Bongo family for nearly 50 years, has been wracked by violent protests after the sitting president was declared the winner of the August 27 polls.

Bongo's rival Jean Ping, a veteran diplomat, took his challenge of the result -- which gave Bongo a winning margin of a mere 6,000 votes -- to the country's top court.

Riots broke out following the August 31 announcement of the results, the National Assembly was torched and there were attacks on Ping's headquarters. Bongo meanwhile claimed that Ping had instigated the violence.

Ping has asked for a recount in the ruling family's stronghold of Haut-Ogooue province, where Bongo won more than 95 percent of votes on a reported turnout of more than 99 percent.

Ping says more than 50 people were killed in post-electoral violence, but the interior ministry says the toll was three dead.

Meanwhile, anxious Gabonese awaiting news of the Constitutional Court's decision on Ping's appeal now only have recourse to the country's tightly-controlled state media and television.

"To know what's really happening we have to wait for the evening news on international TV channels," said a student who identified herself as only Marie.

Another young woman, Laure, said she had "anticipated" the crackdown and installed a virtual private network or VPN on her smartphone to avoid "censorship."

"We have access to Facebook," said the 23-year-old Ping supporter.

Communications Minister Alain-Claude Bilie-By-Nze told AFP that the erratic services were due to "disruptions" in the network and nothing more.

"We are all victims," he said. "Like everybody else, we too cannot work normally and we hope that the links will be re-established quickly," he said.

But this line fails to convince many.

"The government is trying to make us believe that business is back to normal but that's rubbish," exclaimed Paul, who works in a Libreville bank.