In early morning trading, Mediclinic was by far and away the top FTSE 100 gainer, leaping over 18%, or 136p higher to 867p.
In a statement, the Middle East-focused private healthcare group noted reported comments by the crown prince of Abu Dhabi ordering the waiving of a 20% co-payment for holders of a Thiqa medical insurance card when receiving treatment at private healthcare facilities in Abu Dhabi.
The Health Authority of Abu Dhabi (HAAD) had introduced the 20% co-payment for Thiqa patients, those covered by health insurance for UAE Nationals or others of similar status in the country on 1 July 2016.
Mediclinic said it is awaiting precise details on these regulatory changes from HAAD and will continue to monitor the regulatory environment and the effect of these changes on its Middle East business.
Mediclinic bought a group of hospitals in Abu Dhabi in 2015
In an update earlier this month, Mediclinic said trading for the 2017 financial year was in line with expectations, apart from its Abu Dhabi business.
It added that the Abu Dhabi business underperformed due to regulatory changes and certain business and operational challenges.
Mediclinic bought a group of hospitals in Abu Dhabi in 2015 through a reverse takeover of Al Noor Group Hospitals.
The group operates six hospitals and 34 clinics in the UAE, and its Mediclinic Middle East business contributed 16% of revenue for its financial year ended in March.