Iran is looking to offer up to $4.5 billion in rial and foreign currency-denominated bonds by March 2018.
Iranian authorities have been keen to attract foreign investors after the end of sanctions on the country.
Parliament approved on Saturday an item in the state budget for the Iranian year starting on March 21, which allows the Oil Ministry to issue $3 billion worth of the rial and foreign-currency-denominated bonds.
Under another budget line passed on Saturday, the ministry can issue up to 50 trillion rials ($1.5 billion) worth of the bonds, it added.
According to the text of the proposed budget, the $3 billion in bonds are to be used to repay ministry debts for existing projects and the $1.5 billion bonds are to be used to finance new oil and gas projects.
After being passed by parliament, the entire budget has to approved by the Guardians Council that vets legislation before it becomes law.
Iran has signed a flurry of deals with Western companies over the past year since the easing of international sanctions on Tehran after an accord was reached over its nuclear program.
Iran needs foreign investment for repairs and upgrading of its oil and gas fields. It also seeks the transfer of technology to its oil industry after a decade of sanctions.
In November 2016, France's Total became the first oil major to sign a big deal with Tehran since the lifting of sanctions and agreed to help it develop the world's largest gas field, South Pars.
Shell signed a provisional deal in December to develop Iranian oil and gas fields South Azadegan, Yadavaran and Kish in December 2016.
Iran has named 29 companies from more than a dozen countries as being allowed to bid for oil and gas projects using the new, less restrictive contract model.
The firms include Shell, France's Total, Italy's Eni, Malaysia's Petronas and Russia's Gazprom and Lukoil, as well as companies from China, Austria, Japan among other countries.
Russia's Zarubezhneft signed an MoU for a feasibility study on two joint fields in the west of the country.
Norway's International Aker Solutions Company signed an MoU to modernize Iran's oil industry.
Austria's OMV signed in May an MoU for projects located in the Zagros area in western Iran and the Fars field in the south.
South Korean Daewoo Engineering and Construction (Daewoo E&C) signed an MoU to construct an oil refinery in Bandar Jask, on the southern coast of Iran.
Italy's Saipem signed MoUs to cooperate on pipeline projects, upgrading of refineries and development of Tous gas field in the northeastern province of Khorasan Razavi.
Norwegian oil and gas company DNO said it was the second Western energy company after Total to sign a deal with Iran under which it agreed to study the development of the Changuleh oilfield in western Iran.
Lukoil, Russia's second biggest oil producer, hopes to reach a decision on developing two new oilfields in Iran.
Germany's Siemens AG signed an MoU in May to overhaul equipment and facilities at Iran's oil operations and refineries.
BASF's Wintershall oil and gas exploration subsidiary signed an MoU with the National Iranian Oil Company in April 2016.
