The State has now issued a Notice of Arbitration to the Company which asserts that Nautilus has not met certain obligations on which completion of the transactions contemplated by the Agreement is dependent, that Nautilus has breached the Agreement and that the State is entitled to terminate the Agreement. Nautilus has and continues to refute these assertions and maintains that it is the State who has breached the Agreement, not Nautilus.

As previously disclosed, under the Agreement the State’s nominee (a subsidiary of Petromin PNG Holdings Limited) must pay (among other amounts) its share of costs incurred in the development of the Project up to completion to acquire its Project interest (see links section for full press release). Unless and until the dispute is resolved, completion will be delayed or may not occur and Nautilus must continue to carry these costs. This may lead to Nautilus needing to slow or defer the build program for Project equipment, which would have consequential impacts on the scheduled commencement of operations and overall Project costs.

Nautilus will continue to attempt to resolve the dispute with the State in an effort to avoid a costly arbitration process. On completion of its review of the Notice and further meetings in PNG, Nautilus will provide further details of its plans by Friday, June 29, 2012.

Links

http://www.nautilusminerals.com/s/Media-NewsReleases.asp?ReportID=449316&_Type=News-Releases&_Title=PNG-Government-Confirms-Investment-in-Solwara-1

http://www.nautilusminerals.com/s/Media-NewsReleases.asp?ReportID=528424&_Type=News-Releases&_Title=Nautilus-dispute-with-the-State-of-PNG

http://www.nautilusminerals.com/s/Media-NewsReleases.asp?ReportID=531617&_Type=News-Releases&_Title=Nautilus-continues-discussions-to-resolve-dispute-with-State-of-PNG

Certain of the statements made in this news release may contain forward-looking statements within the meaning of the United States Securities Exchange Act of 1934 and forward-looking information within the meaning of applicable Canadian securities law. Forward-looking statements and forward-looking information include, but are not limited to statements or information with respect to the resolution of Nautilus’ dispute with the State, the completion of the agreement and the payment to Nautilus of the amounts provided for thereunder. We have made numerous assumptions about the material forward-looking statements and information contained herein including good faith negotiation by the State, a shared determination to resolve the dispute and the State’s ability to pay the amounts due to Nautilus under their agreement with respect to Solwara 1. Even though our management believes the assumptions made and the expectations represented by such statements or information are reasonable, there can be no assurance that the forward-looking statement or information will prove to be accurate. Forward-looking statements and information by their nature involve known and unknown risks, uncertainties and other factors which may cause the actual results to be materially different from any future results expressed or implied by such forward-looking statements or information. Such risks, uncertainties and other factors include, among others, the risk that negotiations with the State are not productive. Should one or more of these risks, uncertainties or other factors materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in forward-looking statements and information. Although we have attempted to identify factors that would cause actual results to differ materially from those described in forward-looking statements and information, there may be other factors that cause actual results, performances, achievements or events not to be as anticipated, estimated or intended. Also, many of the factors are beyond our control. There can be no assurance that forward-looking statements or information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly you should not place undue reliance on forward-looking statements or information. Except as required by law, we do not expect to update forward-looking statements and information as conditions change and you are referred to the full discussion of the Company’s business contained in the Company’s reports filed with the securities regulatory authorities in Canada.

About Nautilus Minerals Inc.

Nautilus is the first company to explore the ocean floor for polymetallic seafloor massive sulphide deposits and is developing its first project at Solwara 1, in the territorial waters of Papua New Guinea, where it is aiming to produce copper, gold and silver. The company has been granted all necessary environmental and mining permits.

Nautilus also holds approximately 600,000 km² of highly prospective exploration acreage in the western Pacific; in PNG, the Solomon Islands, Fiji, Vanuatu and Tonga, as well as in international waters in the eastern Pacific.

A Canadian registered company, Nautilus is listed on the TSX:NUS and AIM:NUS stock exchanges and OTCQX: NUSMF. Its corporate office is in Brisbane, Australia. Its major shareholders include Metalloinvest, the largest iron ore producer in Europe and the CIS, which has a 21% holding, global mining group Anglo American, which holds an 11% interest and MB Holdings, an Oman based group with interests in mining, oil & gas, which holds a 9.98% interest.