The Arctic region has been described as exceptionally sensitive to climate change which is evidenced by the extremely rapid decline of its sea ice cover. Changes in the sea-ice extent and thickness will affect the distribution of primary production and therefore the entire food web. Besides the phytoplankton in the surface waters of the Arctic Ocean, sea ice algae contribute to primary production, but our knowledge about their activity, especially in the central basins, is still limited. Of special interest for future predictions of the Arctic carbon cycle is the question which factors are limiting primary productivity both in the water column and in the ice, and if the sea ice retreat has positive or negative consequences for Arctic productivity. This study provides recent data from the central Arctic, collected during August and September 2011 on board of the RV Polarstern (TransArc 2011). The relative contributions of sea ice algae, phytoplankton and melt pond phototrophs to primary productivity were measured using the 14C method, along a transect from Atlantic to Pacific waters. The preliminary results show low productivity rates for the phytoplankton in the ice-covered surface waters (0,1-10 µg C/L d) and a high spatial variability for ice (0,8-110 µg C/L d) and melt ponds (0,5-5000 µg C/L d). Surprisingly, the highest rates were found at the surface of the ice floes and in algal aggregates found in the melt ponds. Regarding the nutrients, the very low N:P ratio (0,3-6) across the entire Atlantic transect indicates a general nitrogen limitation; however, primary productivity was mostly related to silicate concentration . These results contribute to broaden our understanding of the biogeochemical and ecological processes taking place in the Central Arctic at the end of the ice melt season and will help to estimate the contribution of sea ice to the carbon budget of the Arctic Ocean