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July 31 (Reuters) - Moderna MRNA.O plans to trim roughly 10% of its global workforce by the end of the year to cut costs amid declining sales of its COVID-19 vaccines, the company said on Thursday.

"By the end of the year, we expect to be fewer than 5,000 colleagues strong," Moderna CEO Stephane Bancel said in a memo to employees.

Earlier this year, the Cambridge, Massachusetts-based company had laid out plans to cut its operating costs by as much as $1.7 billion by 2027. It expects operating costs to be between $4.7 billion and $5 billion for 2027.

"We've made significant progress by scaling down R&D as respiratory trials conclude, renegotiating supplier agreements, and reducing manufacturing costs," Bancel said in the memo.

He reiterated the company's target to have eight more approvals for its products in the next three years.

(Reporting by Bhanvi Satija in Bengaluru; Editing by Shilpi Majumdar)

((Bhanvi.Satija@thomsonreuters.com; Outside U.S. +91 9873062788;))