Workers have been evacuated from buildings in Dubai and Abu Dhabi after the second deadly earthquake in the region in eight days.
At least 40 people are dead in Iran and five in Pakistan, with hundreds more casualties also feared, authorities have told local media.
Officials have declared a state of emergency in the region, describing the quake as the worst in 40 years.
All communications in the area have been cut and rescuers and assessment and evaluation teams from the Iranian Red Crescent Society have been dispatched, the Iranian Red Crescent's Mahmoud Mozaffar told state television.
"In the aftermath of this earthquake five evaluation teams from the Khash and Saravan branches were sent to the area to assess damage," Mozaffar said.
The 7.8-magnitude earthquake was recorded on the border of Iran and Pakistan at 2.45pm UAE time, according to the United States Geological Survey (USGS). The magnitude had earlier been recorded as 7.2.
The quake was felt across the Middle East and Asia, with reports of buildings shaking and people running onto the streets in New Delhi, India. Tremors also were felt in Quetta and Karachi in Pakistan, Dubai, Abu Dhabi and Qatar, with hundreds of people evacuated from shaking buildings.
Dubai Airports took to Twitter to allay concerns that flights had been delayed.
“Passenger operations unaffected by tremors in the UAE, no damage to facilities reported. #Earthquake,” it posted in a tweet.
Meanwhile, in Bahrain, the Minister of Interior said the Chief of Public Security had activated the Disaster Management Centre in response to the earthquake.
The epi-centre was 86km from the remote town of Khash in Sistan Baluchistan province, Iran, according to USGS. About 56,000 people are believed to live in Khash, while another 58,000 are estimated to live in nearby Saravan.
It follows a powerful earthquake that struck close to Iran's only nuclear power station on April 9, killing 37 people and injuring 850 as it destroyed homes and devastated two small villages.
The 6.3-magnitude quake totally destroyed one village, according to a Red Crescent official, but the nearby Bushehr nuclear plant was undamaged, according to Iranian officials and the Russian company that built it.
Iran sits on numerous fault lines and is prone to earthquakes.
More than 26,000 people died in 2003 when a 6.6-magnitude earthquake struck the Iranian city of Bam and the surrounding Kerman province.
More to follow