All schools, including government, private-run and those under civic bodies, which were to reopen tomorrow after the summer vacation, have been told to extend the vacation till July 8.
Now the schools will reopen on July 9.
"We have decided to extend the summer vacation by one week and schools will reopen on July 9 instead of tomorrow," Delhi Education Minister Arvinder Singh Lovely said.
The vacations had started on May 12.
Lovely said, "Non-compliance of the order will be viewed seriously."
The city has been in the grip of heat wave for the last few weeks with the maximum temparature oscillating between 44 and 42 degrees Celsius.
"Due to high temperature and extreme hot weather conditions in Delhi, it is hearby ordered that all government, government aided and unaided recognised schools under Directorate of Education will remain closed upto July 8.
"All MCD, NDMC and Delhi Cantonment Board schools and aided and unaided recognised schools under these local bodies are also directed to remain closed upto July 8," said an order issued by the Education department.