While Aramco is expected to list first on the local Saudi exchange, the company is also considering London, New York and Hong Kong.

"I don't see 2018 as a necessary year to list unless it's optimum," he said.

"What remains is the selection of a potential secondary venue and the timing, and like I said we need to make sure the markets are ready to do that," said al-Falih. "We're ready to do it in the second half if we determine the timing is optimum." But he added if it slips, that is not a problem.

He said the initial pubic offering of the world's largest energy company could be this year, but it could also be later. Aramco is expected to be listed first on the local Tadawul exchange in Saudi Arabia, according to industry sources.

Saudi Energy Minister Khalid al-Falih told CNBC that Saudi Aramco is ready to go public but the company and kingdom will wait for the "optimum" time.

Al-Falih said that the kingdom is ready for the IPO from a regulatory standpoint, and that Saudi Aramco is preparing its 2017 results in line with international standards.

The energy minister also discussed the kingdom's relationship with Russia, which has grown closer since the two agreed to join with OPEC and other producers to curb oil production.

"I think cooperating and sharing experiences in technology while encouraging Russian supply companies to come in and invest in the kingdom is an area we started working on, and I think you'll be hearing about Russian investment in the supply chain in Saudi Arabia," he said.

Al-Falih said the Aramco IPO is expected to attract Russian capital, pooling it from investors, pensions and individuals. "The IPO is going to be open to all investors and Russian capital that is looking to invest wisely in companies with great reputations and potential. We believe Saudi Aramco is going to be on top of its list," he said.

"It's similar to what we've seen from every major economy. Every major economy is already looking at Aramco as a very attractive outlet for their investment," he said.

Al-Falih said the current production agreement between OPEC and other producers has been good for the kingdom and Russia, as well as others including U.S. shale. OPEC is expected to meet with Russia in June to discuss their current agreement to hold 1.8 million barrels a day from the market.

"We will review in June what are the specific targets for a balanced market," al-Falih said. He said even if the market is balanced, the producers may not want to "lift our hands from the steering wheel and leave the market without stewardship" because it could quickly become out of balance.

Al-Falih is in the U.S., along with other Saudi officials, as Crown Prince Mohammed Bin Salman visits Washington and other U.S. cities, to shore up relations and seek investment opportunities.

Al-Falih is the chairman of Saudi Aramco, which is expected to go public as the centerpiece in a plan to diversify the kingdom's economy away from oil.