BERLIN, Nov 19 (Reuters) - Germany"s government will limit shipments of the Biontech/Pfizer (PFE.N)COVID-19 vaccine in the coming weeks to push the use of its stock of Moderna vaccines before it expires, a health official was cited as saying by RND newspaper group on Friday. Health ministry state secretary Thomas Steffen wrote to Germany"s states that 90% of orders curently were for the Biontech vaccine. "But the Moderna vaccine should increasingly be used for boosters because otherwise, we face the expiry of our Moderna vaccines in stock from the middle of the first quarter of 2022," Steffen was quoted as saying. (This story has been refiled to correct typo to read Biontech not Biotech in headline)