May 21 (Reuters) - AstraZeneca CEO said on Tuesday the company has to consider the possibility of supply chain problems related to U.S.-China tensions and for that reason is trying to build a supply chain focused on the China market.

Pascal Soriot was speaking at a press conference on the sidelines of the company's first investor day since 2014.

He cited the company's $450 million investment, announced last year, in a factory in Qingdao, China making inhalers to treat "smoker's lung" as one example of this strategy.

"Until now we only had one plant for the world, based in Europe", for this product, he said.

AstraZeneca is the biggest pharmaceutical company by sales in China, the world's No.2 pharmaceuticals market behind the United States.

Emerging markets account for 29% of AstraZeneca's total revenue, Soriot said in a presentation to investors earlier in the day. (Reporting by Maggie Fick; Editing by Shilpi Majumdar)