BRUSSELS, Jan. 28 – Prime Minister Yulia Tymoshenko threatened on Monday to run for the presidency next year if disagreements between President Viktor Yushchenko and her government continue to persist or worsen.

Tymoshenko, who opinion polls show is more popular than Yushchenko, has been widely said by her opponents to be planning to run for the presidency. She had persistently denied the plans.

But now, speaking in Brussels, Tymoshenko said her decision will actually depend on Yushchenko.

“If our cooperation with Viktor Andriyovych Yushchenko is harmonious and balanced, if a single joint approach is demonstrated towards solving problems, there is no sense to nominate two candidates from the democratic coalition,” Tymoshenko said.

“Then I, with my limitless love to Ukraine, can support [Yushchenko]. But this must be a two-way street,” Tymoshenko said.

The comments come a day after Yushchenko publicly accused Tymoshenko of seeking to sell power assets through non-transparent deals to opposition lawmakers to increase legislative support for her initiatives.

Yushchenko threatened to take “an immediate” action if the deals come through.

The allegation is the second major disagreement between Yushchenko and Tymoshenko over the past two weeks.

Both clashed publicly over whether to restart talks with Russia over natural gas supplies to Ukraine. Yushchenko insisted that gas supply arrangements must be left intact for 2008, while Tymoshenko has been seeking to reopen the talks.

Yushchenko even forced Tymoshenko to postpone, for almost a month, a planned visit to Moscow, seeking to prevent the reopening of the talks. Tymoshenko is now due on Feb. 21 to visit Moscow, while her Jan. 23 visit has been cancelled.

Meanwhile, Tymoshenko, in Brussels, sought to play down at least some disagreements with Yushchenko, in particular their differences on the gas talks with Russia.

“We have a joint view that the value of transit is not market-based,” Tymoshenko said. “If the gas price is approaching the market level, then the cost of transit must also come closer to the market level.”

Yushchenko, while voicing concerns over the reopening of gas talks, suggested the move may backfire by further increasing the price of gas for Ukraine. Analysts said the development may also disrupt supplies of gas to the EU.

Tymoshenko assured EU officials said she “will not make any drastic move,” in order to ensure “the stability of European gas supplies.”

The development underscores difficult relations between Yushchenko and Tymoshenko, considered Ukraine’s two most pro-Western political figures, highlighting pressure the government may face in the future.

The friction put pressure on the coalition, which controls a slim majority of 227 seats in the 450-seat Parliament. (tl/ez)