Indonesia will hold tenders for unused spectrum in the 2.1GHz and 2.3GHz bands and name winners by the middle of the year according to Rudiantara, the country’s Communications and Informatics Minister.

Rudiantara, who like many Indonesians goes by one name, said guidelines for the tender will be issued by the end of March and only existing players can participate, the Jakarta Globe reported.

He said mobile operators are facing a “spectrum crunch” as data demand soars in major cities in Java and the additional bandwidth will allow them to improve their capacity in densely populated areas.

The sale of unused 2.1GHz spectrum has been delayed since 2015. Two unused frequency blocks of 10MHz were returned to the government in 2014 after a merger between XL Axiata and Axis.

The newspaper said just 15MHz of the 30MHz of unused 2.3GHz spectrum will be available in the tender.

3 Indonesia director Danny Buldansyah said he hopes for no further delays in holding the tender and noted that government could generate as much as IDR700 billion ($52.5 million) in revenue, including up-front fees, in the first year of operation from the sale of one 5MHz block, the Globe reported.