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April 28 (Reuters) - China's state-run Sinopec 600028.SS said on Monday it had signed an agreement with a unit of Saudi Aramco 2222.SE to establish a joint venture company with a registered capital of 28.80 billion yuan ($3.95 billion).

The agreement was signed by Sinopec, its unit Fujian Petroleum Chemical Industry Co, and Saudi Aramco's Singaporean unit Aramco Asia Singapore Pte.$(AAS.UK)$.

Sinopec and its unit shall contribute 7.20 billion yuan and 14.40 billion yuan in cash, respectively. The remaining amount, representing 25% of the registered capital of the joint venture, will come from AAS.

The joint venture company, Fujian Sinopec Aramco Refining and Petrochemical Co, will engage in port operation, crude oil transportation, and other activities at the refinery and petrochemical complex in the Gulei Port Economic Development Zone, Zhangzhou, in China's Fujian province.

Sinopec and Saudi Aramco started constructing the complex in November last year, as part of the Middle Eastern company's plans to grow its downstream business outside the kingdom and to supply a million barrels per day of crude oil to China for oil-to-chemicals investments.

Sinopec, in a separate statement, reported a 27.6% drop in first-quarter net profit under the China Accounting Standard on Monday.

($1 = 7.2975 Chinese yuan renminbi)

(Reporting by Sherin Sunny in Bengaluru; Editing by Devika Syamnath)

((Sherin.Sunny@thomsonreuters.com;))