The Russian rouble closed on Wednesday at its strongest this month against the dollar both in Moscow and offshore exchanges after President Vladimir Putin said Russia would start selling its gas to “unfriendly” countries in roubles. The rouble ended below 100 per dollar, still down over 22 percent this year as Russia faces strict sanctions globally, triggered by its invasion of Ukraine late last month. European gas prices soared after Putin’s shock announcement, on concerns the move would exacerbate the region’s energy crunch. “It seems to be an effort by the Russian authorities to apply pressure on Western countries by forcing foreign buyers of Russian gas to use roubles, with the added benefit of supporting the value of the currency,” said Liam Peach, Emerging Europe economist at Capital Economics in a client note. The rouble gained 6 percent to close at 97.7375 per dollar in Moscow after touching 94.9875, its strongest since …