Passage: On 24 January 2005, Tymoshenko was appointed acting Prime Minister of Ukraine under Yushchenko's presidency. On 4 February, Tymoshenko's premiership appointment was ratified by the parliament with an overwhelming majority of 373 votes (226 were required for approval). She is the first woman appointed Prime Minister of Ukraine.The Tymoshenko cabinet did not have any other members of Tymoshenko's party besides Tymoshenko herself and Oleksandr Turchynov, who was appointed the chief of Security Service of Ukraine. The ministers who were working with her took her side in the later confrontation with Viktor Yushchenko.On 28 July, Forbes named Tymoshenko the third most powerful woman in the world, behind only Condoleezza Rice and Wu Yi. However, in the magazine's list published on 1 September 2006, Tymoshenko's name was not among the top 100.Several months into her government, internal conflicts within the post‐Revolution coalition began to damage Tymoshenko's administration. On 24 August 2005, Viktor Yushchenko gave an Independence Day speech during which he called Tymoshenko's government "the best".Yet on 8 September, after the resignation of several senior officials, including the Head of the Security and Defense Council Petro Poroshenko and Deputy Prime Minister Mykola Tomenko, Tymoshenko's government was dismissed by President Viktor Yushchenko during a live television address to the nation. Yushchenko went on to criticize her work as head of the Cabinet, suggesting it had led to an economic slowdown and political conflicts within the ruling coalition. He said that Tymoshenko was serving interests of some businesses, and the government decision to re-privatize the Nikopol Ferroalloy Plant (previously owned by Leonid Kuchma's son in law Viktor Pinchuk) "was the last drop" that made him dismiss the government. On 13 September 2005, Yushchenko accused Tymoshenko of betrayal of "Orange Revolution" ideas. In his interview for the Associated Press, he said that during the time of her presidency at UESU, Tymoshenko...

Question: Who is president of Ukraine here?
Yushchenko