LONDON—The safe-haven Japanese yen fell back on Friday and risk-sensitive currencies, such as the Australian dollar advanced as investors took comfort from a plan to hold talks between the United States and Russia over the crisis in Ukraine. The euro edged higher against a weaker dollar. The yen and rival safe haven, the Swiss franc, have gained this week with investors unsettled by rising tensions on the Ukrainian border, where Russia deployed more than 100,000 troops. Western powers say Russia is looking for a pretext to invade, a charge Moscow rejects. Sentiment improved after news late on Thursday that U.S. Secretary of State Antony Blinken had accepted an invitation to meet with Russian Foreign Minister Sergei Lavrov late next week provided Russia does not invade Ukraine. This followed a jittery Thursday when Kyiv’s forces and pro-Russian separatists exchanged fire. Risk Appetite Subdued “The confirmed meeting between Blinken and Lavrov may …