"We are asking IMF to extend budget support," Jayasundera told reporters in Colombo.
"That money cannot go the central bank."
The IMF usually gives a loan to a central bank to boost external monetary reserves with fiscal funding being left to the World Bank.
Money that goes to foreign reserves cannot be spent domestically and is usually invested in US or other liquid debt in reserve currency countries effectively financing their deficits.
Jayasundera said Sri Lanka had adequate foreign reserves but if IMF willing to give cheaper funds for development spending, Sri Lanka would welcome it.
This year Sri Lanka is not expected to sell a sovereign bond in international capital markets.
An IMF team is due at the end of the month on a two week visit for annual so-called 'Article IV' consultations.
The loan would be discussed at that time, Jayasundera said.