June 4 (Reuters) - U.S.-based specialty chemicals maker Celanese CE.N said on Thursday it would shut its engineered materials plant in Ulsan, South Korea, and shift production to sites in China and India as part of efforts to streamline operations.

The company said manufacturing at the Ulsan site would cease immediately, with volumes transferred to its facilities in Nanjing and Shenzhen in China and Silvassa in India, as it looks to cut costs.

The announcement comes as chemical companies face uneven demand and margin pressure, particularly in industrial and automotive end-markets, prompting them to rationalize capacity.

Supply disruptions following the Iran conflict have tightened global chemicals markets, pushing plastics and polymer prices to multi-year highs.

In March, Celanese increased prices for a range of engineered materials products, citing global supply chain disruptions.