Service to social media platforms Facebook, WhatsApp and Instagram has been restored in Ethiopia after they were restricted earlier on Monday, internet blockage observatory NetBlocks said.

"Service to impacted online platforms in Ethiopia has been restored as of Monday mid-morning," NetBlocks said. "We continue to monitor."

Earlier on Monday, the London-based watchdog had said in a tweet that network data had showed that Facebook, WhatsApp and Instagram had been restricted in Ethiopia. Its director Alp Toker told Reuters that NetBlocks observed the restrictions at six locations across Ethiopia.

The head of Ethiopia's Information Network Service Agency, Shumete Gizaw, did not immediately respond to phone calls and text messages seeking comment on Monday morning.

State-run telecommunications monopoly Ethio Telecom chief executive Frehiwot Tamiru also did not immediately respond to phone calls and text messages seeking comment.

Platforms including Twitter, YouTube, Snapchat, LinkedIn and Reddit had remained available, Toker said in an email. Users with access to VPN services were able to work around the restrictions, he added.

Ethiopia's electoral board said on Saturday that it was postponing June 5 parliamentary elections to an unspecified date due to logistical challenges, the second time the vote has been delayed after the initial August 2020 date was scrapped because of the Covid-19 pandemic.

Access to the internet in Ethiopia has been restricted in the past during periods of political unrest, including in the northern region of Tigray last year after the military launched an offensive against regional forces that attacked its bases there.

After an internet blackout in June 2019, NetBlocks estimated that it had cost the country's economy $17-million.