Her comments appeared to be aimed at Yushchenko, whose party pulled out of Tymoshenko's governing coalition and who has since accused her of "treason" by putting her own interests ahead of those of the state.
Tymoshenko, however, also held out the prospect of a reconciliation with Yushchenko's Our Ukraine party and said the coalition could be renewed "within a week".
Members of the former ruling coalition met on Wednesday to negotiate how they might revive their pro-Western alliance and avoid the early elections.
Yushchenko can dissolve parliament if a new coalition is not formed or the old one is not revived by mid-October.
Yushchenko and Tymoshenko have had a tenuous relationship since 2004, when they joined forces to overturn a rigged election in a series of mass street protests known as the Orange Revolution.
Their latest split was sparked by differences over how Ukraine should react to Russia's war with Georgia.
Yushchenko pulled his Our Ukraine party from the ruling coalition after Tymoshenko's party joined forces with the pro-Moscow opposition to pass legislation limiting the president's powers.
Tymoshenko then said she would not resign as prime minister, a refusal Yushchenko said violated their coalition agreement.
Separately, Tymoshenko said she expected Ukraine to sign a deal by next month with Russia on the delivery of gas starting from 2009.
"I am very hopeful of being able to sign this agreement before the end of October and it will not be for a year but for a prospective period of three to four years," she said.
In July, Tymoshenko said she had reached a framework agreement with Russian gas giant Gazprom on the politically sensitive issue of boosting the price of gas deliveries.