When Saudi Arabia and Russia sat down to talk about limiting oil production 14 months ago, the discussions to stem a collapse in prices did not get very far.  “The minister confirmed that Russia was not willing to cut,” Ali al-Naimi, Saudi Arabia’s powerful energy minister later said about the meeting in a plush Vienna hotel. “We said ‘thank you’ and the meeting was over.”  Days later Mr Naimi upended the oil industry, forcing through a decision at Opec headquarters to keep the taps open and put pressure on rival producers outside the cartel.  For many oil market watchers, the outcome would be no different if the two energy super powers met again today, even though prices have fallen by more than half since that fateful meeting in November 2014  While signals from Moscow this week about a willingness to entertain conversations about a collaboration with Opec producers excited traders — sending oil prices up more than 8 per cent — oil executives in Russia and Opec officials remain wary.