KIEV, April 16 - The standoff between President Viktor Yushchenko and Prime Minister Yulia Tymoshenko turned ugly Wednesday when her group accused the president of "shaming" Ukraine and being the main "threat" to its independence.

Our Ukraine, Yushchenko's group and Tymoshenko's coalition partner, responded with a harsh warning that the wording used was "unacceptable" for civilized political leaders.

The development is the latest in the rapidly worsening relations between Yushchenko and Tymoshenko over the pace of economic reforms and over Ukraine's future political system and constitution.

The rivalry between the two has been stemming from the understanding that both will be running for the presidency next year.

Yushchenko fears Tymoshenko's plans to run for the presidency has been postponing vital economic reforms, such as liberalization of domestic natural gas prices, which would badly hurt her support rating.

Instead, Tymoshenko has come up with a campaign to pay out billions of hryvnias to millions of people on failed Soviet-era bank deposits, the campaign that has boosted her rating.

But the bailout and the injection of billions of hryvnias have also spurred inflation to the level that has now been threatening economic stability, the presidential office charged.

Now, with the campaign apparently running out of cash, Tymoshenko has been seeking to sell more state assets to raise money to keep up high pace of social payments ahead of the presidential election.

But Yushchenko used his authority to suspend the privatization spree, which he argues has been lowering prices of assets and further fueling inflation.

This angered Tymoshenko as her failure to carry out te promised bailout may in fact hurt her support rating significantly.

"President Yushchenko, for the sake of maintaining illusive chances to win at the next election, has started the total elimination of all beginnings and initiatives of the democratic government," the Tymoshenko group said in a statement.

"It's a pity that the activity of the president has become one of the main threats to the independence of Ukraine, to its sovereignty," the group said.

"The president of Ukraine has been systemically shaming Ukraine making statements that humiliate the dignity of Ukraine in the world," the Tymoshenko group said.

Our Ukraine rushed to defend the president.

"The tone that the Tymoshenko Bloc used in its assessment of the activity of the President of Ukraine is unacceptable for civilized politicians whatsoever, not to mention the political group that is a coalition partner of the pro-presidential party," Our Ukraine said in the statement.

"We remind our partners that President Yushchenko has been elected the Head of State by the people," Our Ukraine said. "It was Yushchenko who brought unity to democratic groups, dismissed corrupt Parliament and made sure the early election takes place."

"We urge the Tymoshenko Bloc to restrain emotions and focus on effective work that the people have been waiting for," Our Ukraine said. (tl/ez)