Pars Oil and Gas Company financial director Touraj Jahanara made the announcement in an interview with the Shana news agency.
Last year, around $20 billion was allocated for the purpose, Jahanara added.
He said the highest investments last year were made in the phases 12, 22-24, and 13 of the South Pars.
Deputy Oil Minister Mohsen Khojasteh-Mehr said in October 2011 that development of the South Pars is a priority, and funds will be channeled there for as long as necessary.
In 2009, Iran said development of the remaining phases of South Pars required $40 billion investment over 10 years.
The South Pars gas field is shared by Iran and Qatar. The Iranian share, which is divided into 29 phases, has about 14 trillion cubic meters of gas, or about eight percent of the total world reserves, and more than 18 billion barrels of liquefied natural gas resources.
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