SPIELBERG, Austria - Formula 1 engine Renault has tipped rumours about its future to eventually "disappear".In the paddock at the 2014 Austrian GP, Red Bull's own circuit, rumours have been swirling that Red Bull is planning to dump struggling Renault in order to build its own F1 power unit.And a related rumour is that, if that does happen, Renault could simply quit F1 altogether. Responding to the rumours in Austria, Renault Sport F1 chief Jean-Michel Jalinier said: "We have a three-year supplier contract with Red Bull, which runs to the end of 2016.'RUMOURS WILL DISAPPEAR'"The cooperation between the two technical teams is going very well. We are developing the 2014 engine to catch up with the competition."At the same time, we are putting a lot of work into the power unit for 2015. I am convinced that we will catch Mercedes in 2014 and, that we will have a very competitive car in 2015 in conjunction with the chassis."Then these rumours will disappear."However, it has been suggested that the only way Renault will be able to appease Red Bull and end all the suggestions about a bespoke engine, is to ditch the flawed 2014 package and start afresh for 2015 - perhaps with a Mercedes-like concept.Jalinier said: "It (the 2015 engine) is more evolution than revolution. But of course, we use the entire scope of the regulations to promote our development."