The Russian rouble traded on the stronger side of the 90 mark against the U.S. dollar on Thursday following U.S. President Donald Trump's criticism of Ukrainian President Volodymyr Zelenskiy.

At 1000 GMT, the rouble was up 1.1% at 88.70 against the dollar in the over-the-counter market, maintaining a break of the 90 level in a sustainable way for the first time since September.

"More positive geopolitical news could push the rouble even higher," Alor brokerage analysts said in a research note.

The rouble was also up 1.8% at 12.12 against China's yuan, the most traded foreign currency in Russia, in trade on the Moscow stock exchange.

The Russian currency has gained almost 22% against the dollar this year, mostly on expectations of easing geopolitical tensions between Russia and the West.

(Reporting by Gleb Bryanski; Editing by Kirsten Donovan)