The foreign ministry statement comes despite international demands for Iran to halt its nuclear activities.
Tehran says it is refining uranium for electricity generation and medical applications.
Enriched uranium can be used for civilian nuclear purposes, but also to build atomic bombs.
"By installing the new centrifuges progress is being made with more speed and better quality," said spokesman Ramin Mehmanparast.
He said the move showed Iran's success in pursuing its "peaceful nuclear activity".
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