OCI should consider options for its methanol business, its low-carbon ammonia project in Beaumont, Texas, and its Iowa Fertilizer Co unit, the report said, quoting Ubben's letter to OCI Executive Chairman Nassef Sawiris.

It added that the Dutch chemicals maker is worth almost double its 5.5 billion euros ($5.96 billion) market value.

OCI is "both misunderstood and under-analyzed" and is worth about 90% more than its current stock price based on its underlying assets and announced projects, the letter added, according to the report.

Commenting on Ubben's letter, OCI CEO Ahmed El-Hoshy said the company is planning to undertake a review to address the points raised by Ubben and "examine all potential suggestions", the report said, citing an interview with the CEO, adding that El-Hoshy agrees with Ubben that OCI is undervalued.

Inclusive Capital Partners and OCI did not immediately respond to Reuters requests for comment.

The San Francisco-based Inclusive Capital Partners currently owns a 5% stake in OCI, according to Refinitiv data.

($1 = 0.9224 euros)

(Reporting by Anirudh Saligrama and Rishabh Jaiswal in Bengaluru; Editing by Devika Syamnath)