MOSCOW, Dec 20 (Reuters) - European natural gas prices jumped more than 8% on Monday, nearing an all-time high, with Russian deliveries to Germany through the Yamal-Europe pipeline at very low levels. A rapid rise in gas prices in Europe in 2021 has caused power price rises, concerns about the knock-on effect on inflation and triggered the collapse of suppliers in Britain. The Dutch front-month gas contract was at 146.00 euros/MWh, having earlier touched 146.73 euros and with the all-time high record of 155 euros set in October in sight. Flows have diminished, data from German network operator Gascade showed, as Russia"s Gazprom started to fill the second line of the Nord Stream 2 pipeline with gas on Friday, fuelling European power supply concerns. read more "The renewed drop in flows to north-west Europe along one of three main pipelines coincides with both the start of linepacking of string 2 of Nord Stream 2, as well as unseasonably cold weather in Russia," ICIS analysts said. Flows at the Mallnow metering point on the German-Polish border were down to an hourly volume of just around 370,000 kilowatt hours (kWh/h) comparing with more than 1,200,000 kWh/h on Saturday and more than 10,000,000 kWh/h on Friday. Flows on the pipeline, a major route for Russian gas to Europe via Belarus, had been hovering at between 9,000,000 and 12,000,000 kWh/h on average this month. Gascade declined to comment. "Gazprom supplies gas in line with the requests from consumers and in full compliance with the current contractual obligations," Gazprom said. The Russian gas giant has not booked volumes for transit via the pipeline for December and buys the capacity at daily auctions. read more It booked 8.3 million kWh/h of gas transit capacity via the route for January, according to the auction results. Total capacity on offer for January was 38.4 million kWh/h. Transit capacity via Velke Kapusany on the Slovakia-Ukraine border for the Russian gas were booked at 13.168 million cubic metres per day for January. Nominations for Monday"s volumes at the Velke Kapusany metering point, another major route to Europe, were for 953,313.0 megawatt hours (MWh), or 89.97 million cubic metres, similar to levels so far in December. Reporting by Vladimir Soldatkin and Oksana Kobzeva; additional reporting by Nora Buli in Oslo, Anna Koper in Warsaw, Christoph Steitz in Frankfurt and Jason Hovet in Prague; Editing by David Goodman and Alexander Smith