Users of the messenger app began facing issues with sending and receiving messages at around 11am GST, with more than 9,000 users in the UAE reporting problems on website Downdetector.
The issues appeared to be global, with WhatsApp trending worldwide on social media.
Neither WhatsApp nor its parent company Meta gave an explanation for the outage. However, users began receiving messages as normal just before 1pm.
Users were able to open the app, type messages and read existing conversations, but new messages were showing as undeliverable. The problem also affected WhatsApp Web users.
Messages in private chats appeared with one tick, signifying they had not reached the recipient, and messages in groups were not sending at all.
Global glitches for WhatsApp users are rare. However, last October, the messenger platform, along with other Meta-owned apps Facebook and Instagram, suffered at six-hour outage, affecting as many as 2.7 billion people around the world.