The Democratic Republic of Congo's government has ordered telecommunications providers to cut the country's internet and SMS services.
The move comes ahead of planned public demonstrations to protest President Joseph Kabila's refusal to step down at the end of his second and final term in office in December 2016.
While Congo's constitution bars him from running for a third term, Mr Kabila struck a deal with opposition to remain in office until the country's next elections, which should have happened before the end of 2017.
However the date for the elections has been pushed back another year, meaning Mr Kabila can remain in power until December 23, 2018.
Catholic activists called for marches in major Congolese cities to protest Mr Kabila's extended presidency and to demand that he commit to not changing the constitution to allow him to stand for a third term. Activists are also calling for the release of political prisoners.
The governor of Kinshasa, Congo's capital, banned a major protest planned for Sunday (local time) on the grounds that there were not enough police officers to supervise the march.
Telecommunications minister Emery Okundj ordered internet and SMS providers to suspend all services by 6pm on Saturday evening (local time).
He told Reuters the suspension was for "reasons of state security".
"In response to violence that is being prepared... the government has the duty to take all measures to protect Congolese lives."