When I boarded the aircraft, it could be seen from the jetty that there was quite a deposit of snow and ice on the entire span of the wing upper surface. The temperature was probably around freezing, and light snow was falling from time to time. Although on-stand de-icing is the normal procedure at the airport, the engines were started and the aircraft taxied towards the runway holding point. I became more and more worried as it became clear that we are not going to be de-iced before takeoff. We stopped near the runway in queue for departure. I was just about to say something to the cabin crew when the first officer came out of the flight deck and had a look at the wings. I had a quick word with him and said we need to de-ice. Soon after he returned to the flight deck, the captain announced that the aircraft was returning to the stand as he was not happy with the ice on the wing. We departed later after de-icing had been carried out, much to my relief. I think it was very likely that the need to de-ice was made apparent by radio from following aircraft, which prompted the appearance of the co-pilot in the cabin for inspection. I cannot imagine what else would have facilitated this check at this late stage. Whatever it was, I am glad that the last link in the safety chain held on this occasion. 4. Why did the captain announce that the aircraft was returning to the stand?