DUBAI, April 27 (Reuters) - The Abu Dhabi government has cancelled a requirement for its citizens to make a 20 percent co-payment for treatment at private facilities, official news agency WAM said.

This decision is a boon to private healthcare providers in Abu Dhabi, including foreign companies.

Abu Dhabi Crown Prince Sheikh Mohamed bin Zayed al-Nahyan ordered the change, restoring coverage of the government's Thiqa medical insurance scheme to 100 percent, WAM reported late on Wednesday.

He also ordered construction of a medical college and a specialised healthcare district.

International healthcare operator Mediclinic and other foreign companies with investments in Abu Dhabi had been lobbying for the co-payment to be abolished, complaining that it affects their business.

The co-payment, which did not apply to government hospitals, was introduced in July last year. That turned out to be a crucial period for London-listed Mediclinic as it had just bought Abu Dhabi private hospital group Al Noor for about $1.7 billion.

(Reporting by Andrew Torchia; Editing by Sherry Jacob-Phillips) ((andrew.torchia@thomsonreuters.com; +9715 6681 7277; Reuters Messaging: andrew.torchia.thomsonreuters.com@reuters.net))