Ramadan fast lasts 2 mins more on Dubai Burj - mufti

A view of the Burj Khalifa tower in downtown Dubai, May 10, 2011.

DUBAI (Reuters) - Residents of the world's tallest tower, Dubai's Burj Khalifa, have to break their daily dawn-to-dusk Ramadan fast two minutes later than the rest of the city, the city's top cleric said.

At a height of 828 metres (2,716 feet), those on its upper floors can still see the sun after it has gone down over the rest of the Gulf's financial and tourism hub.

Religious authorities insist that Muslims fasting during the holy month must ensure the sun can no longer be seen on the horizon before they break their fast.

"Burj Khalifa is almost one km high, which means people in higher floors can still see the sun after it has set on the ground," Ahmed Abdul Aziz al-Haddad told Reuters on Sunday.

"Therefore, they can't break their fast like the rest of the city, there's a two-minute time difference," said al-Haddad, Dubai's mufti -- a Muslim cleric who issues rulings on questions of religious law and practice.

Haddad said a Muslim cleric faced by a similar problem nearly a thousand years ago, when asked if guards atop the Lighthouse of Alexandria should break their fast with the rest of the city.

"His answer was that they could only break their fast when they see the sun has gone down by themselves," Haddad said.

(Reporting by Mahmoud Habboush; Editing by Louise Ireland)