FILE PHOTO: The logo of commodities trader Glencore is pictured in front of the company's headquarters in Baar, Switzerland, July 18, 2017. REUTERS/Arnd Wiegmann/File Photo

LONDON (Reuters) - Swiss trader and miner Glencore GLEN.L expects to secure U.S. approval by the end of June on the U.S. portion of a deal to sell a 51 percent stake in its storage and logistics business to China's HNA Group, sources familiar with the matter said.

Glencore agreed in March to sell the stake in its petroleum products storage and logistics business for $775 million to HNA Group subsidiary HNA Innovation Finance Group Co, which specializes in commodities, logistics and investment services.

The Swiss firm said on Dec. 29 it had closed parts of the deal worth $579 million but three assets in the United States still required clearance for sale by the Committee on Foreign Investment in the United States (CFIUS).

The filing process with CFIUS began in January.

Approval should take about four months but could stretch to the end of the second quarter because of increased U.S. scrutiny of Chinese companies and their ownership after a rise in Chinese acquisitions in the United States, one of the sources said.

Spokesmen for Glencore, HNA and CFIUS declined to comment.

CFIUS, which scrutinizes deals for potential threats to U.S. national security, has toughened its stance on the sale of U.S. companies to Chinese buyers, blocking deals in sensitive industries and putting others through a prolonged review.

A senior HNA Innovation executive told Reuters on Tuesday that the firm would not chase U.S. deals in 2018 partly due to Washington’s increased scrutiny.

HNA, which began in the aviation industry, has been on a two-year buying spree snapping up assets worldwide from logistics to hotels to banking.