"I want to cooperate with the president, seek constructive cooperation with lawmakers who support him, and serve Ukraine," Tymoshenko was quoted by her press service as saying.
The statement came after Yushchenko's state-of-the-nation address to parliament earlier on Tuesday, when he called on political groups to end their disputes ahead of the presidential election due early next year, and urged joint action to see the country through its economic troubles.
"I am asking for an end to political passions," Yushchenko told the Supreme Rada. "The presidential campaign starts four months before the election, so I am asking you to wait until September before seeking political dividends."
Yushchenko said the country's economic output shrank 25-30% in the first two months of this year, and accused Tymoshenko's government of deliberately covering up the figures.
"We have lost foreign markets that accounted for 60% of Ukrainian exports. Almost all our foreign currency earnings depended on these markets, and the jobs of nearly 2 million people in the steel and chemical industries, and related sectors."
The president demanded that changes be made to the 2009 budget cutting spending, and that new laws be passed to secure International Monetary Fund loans.
Later on Tuesday, the Supreme Rada failed to pass three of the five anti-crisis bills proposed by the government, which were blocked by the pro-presidential Our Ukraine faction. However, premier Tymoshenko said this did not suggest a conflict between her government and the president.
"I would not like this to be seen as a standoff between the president and premier," she said.
Allies in the 2004 "orange revolution" which swept the Western-leaning president to power, Yushchenko and Tymoshenko have long been at odds over a host of issues, most recently over ties with Russia.
Yushchenko accused Tymoshenko of betraying the country's interests in a bitter natural gas dispute with Russia over debt, pricing and transit.
The president and premier, however, both attended talks with the European Union last week on cooperation in the modernization of Ukraine's Soviet-era gas pipeline network. Russia, which supplies most of its EU-bound gas via Ukraine, criticized the talks as disregarding its interests.
Yushchenko and Tymoshenko are both expected to run for president.
