Saudi Arabia has set aside SAR20bn ($5.3bn) for the execution of the first phase of a new metro service in Makkah.
City of Makkah Mayor Osama Al-Bar said: "Work is currently going on the blueprint of the project."
"Six months after that we will start signing contracts for the execution of the project," Al-Bar said.
The metro network will cover all parts of Makkah and is intended to ease transport to the city centre and the Grand Mosque.
The Makkah Metro will compliment the Al Mashaaer Al Muqaddassah Metro, an 18km service that opened in November 2010.
It was built to transport pilgrims between holy sites in Mecca, Mount Arafat, Muzdalifa and Mina to reduce congestion caused by buses and cars during the Hajj.
The Mecca monorail project has been one of many undertaken by Saudi Arabia to expand its railway network to meet the transportation needs of its growing population of 25 million and improve an old-fashioned logistics infrastructure.
According to reports, the line provides transport for about 3.5 million people who arrive at Mecca annually to perform Hajj and the number is expected to increase to five million in future.