Olivier Jakob, managing director at Swiss consultant Petromatrix GmbH, was quoted by Bloomberg News as saying oil export revenues are close to "full capacity."
"With exports close to 1.5 million barrels a day and Brent crude above $110 a barrel Iran does not really care anymore about the sanctions," said Jakob.
Iranian President Mahmoud Ahmadinejad has faced mounting pressure regarding his leadership over an economy that depends on oil export revenue. The national currency collapsed last year under sanctions pressure.
Several countries, led by the United States, imposed sanctions on Tehran because of a perceived refusal to be transparent about Iran's nuclear program. There is a fear the program is designed to develop a nuclear weapon. Tehran says it is solely for peaceful purposes.
Additional sanctions from the United States go into force next week.
Diane Munro, a supply analyst with the International Energy Agency, told Bloomberg that the agency wasn't ready to revise its Iran data until next month. Crude oil shipments from Iran as of Jan. 18 were reported by the IEA at 1.2 million bpd.
The next monthly market report from the IEA is expected Feb. 13. The Organization of Petroleum Exporting Countries releases its next report Feb. 12. OPEC in January reported a decline in Iranian oil production.