Popular messaging application Whatsapp was down for about an hour across many countries this afternoon.

The application owned by Facebook is down since 4pm, but gradually recovered within an hour.

According to DownDetector, a website that provides real-time overviews of the Internet and mobile services, Whatsapp is down across Europe.

However, users reported several other affected countries including Malaysia, UK, USA, India, Saudi Arabia, Philippines and Germany.

According to Reuters, the extent of the outage was not immediately known, but some users reported that WhatsApp, the world's most popular messaging service, had begun to function again about 30 minutes after initial complaints of an outage.

A spokesperson for Facebook in Singapore said the company was investigating the matter.

Whatsappdown was the top trending item on Twitter in India, which is its biggest market with roughly 200 million of its billion-plus users.