Vladimir Putin arrived in China on Tuesday set on increasing cooperation after Russia's relations with the west soured over the Ukraine crisis. But Beijing holds far more cards at the negotiating table, and the most significant deal, a gas export agreement, had yet to be signed as the visit wound down.

Meanwhile, the two countries began joint military exercises in the East China Sea in a clear show of strength against Japan, a western ally that has long-running territorial disputes with both Russia and China.

• The first Russian motherboard based on ARM-processor Baikal-M