Ukraine's next president Viktor Yushchenko was quoted as saying on Wednesday he had agreed to back firebrand politician Yulia Tymoshenko as his prime minister but that did not mean she was certain of getting the job. Yushchenko was elected in Sunday's re-run of a rigged presidential election, defeating Prime Minister Viktor Yanukovich by more than seven percentage points. Interfax Ukraine news agency quoted him as telling local reporters that agreement to back the wealthy businesswoman was part of a deal to win support for his election campaign. "There is an agreement which calls for my group and I to direct our efforts towards mobilising our support for Yulia Volodymyrivna (Tymoshenko) as a candidate," he was quoted as saying. But he added the final decision remained the subject of negotiation. Tymoshenko, a former deputy prime minister dubbed the "gas princess" for her success in the energy business, has played a major role in Yushchenko's election victory, making fiery speeches to vast crowds in Kiev streets. --More 2256 Local Time 1956 GMT