Yanukovich made the comment when meeting with visiting Polish parliament speaker Jozef Oleksy, the national news agency Ukrinform reported.

During the meeting, the Polish speaker raised the issue of whether the southeast part of Ukraine will be separated and said this danger worries Poland.

Yanukovich answered that all things depend on whether the opposition continues to speak in a tone of ultimatum and do thingsagainst the constitution.

He added that if the opposition refuses to compromise, there isa real danger of separation.

On Sunday, Yulia Tymoshenko, an aide to opposition leader and presidential candidate Viktor Yushchenko, demanded that President Leonid Kuchma sack Yanukovich and form a coalition government. Shegave the president 24 hours to dismiss the prime minister and topofficials in three eastern provinces for conducting activities to separate the country.

She threatened the opposition will start to block roads Tuesdayif her demands are not met.

Also on Sunday, a meeting of people's deputies held in the eastern Ukrainian city of North Donetsk warned of seeking trans-regional autonomous alliance and called for a referendum on setting up a "Southeastern Republic".

On the same day, the congress of the eastern Ukrainian provinceof Donetsk decided to hold a referendum on whether to upgrade the province into an autonomous republic on Dec. 5, signaling a move for separation.

According to other reports, representatives from both camps said in Kiev on Monday the hearings held by the Ukrainian Supreme Court on the appeal concerning presidential election frauds would last several weeks.

The Supreme Court on Monday started the hearings on the appeal,which was filed by the opposition camp after the election standoffemerged last week.

Yanukovich's supporters said that it might take two or three weeks for the court to make a final decision, because the whole process is very complicated.

They said that according to the election law, the court cannot annul the whole vote but the election results in some electorates.

The opposition claimed that the court may need a lot of time togo through the large amount of proofs presented by them.

They added that it is possible for the court to make a brave, abnormal decision to annul the announcement by the Central Elections Commission last Wednesday that Yanukovich won the election.

According to the latest development, some parties involved in the standoff have reportedly agreed to the idea of re-organizing the presidential elections.

Ukrainian President Kuchma, who had been silent on the election,made a "U" turn on Monday by proposing holding new presidential elections.

Opposition leader Yushchenko had demanded another round of presidential elections on Dec. 12, while his rival Yanukovich had opposed the idea.

Polish parliament speaker Oleksy, who served as a mediator and met with Kuchma, Yanukovich and Yushchenko on Monday, told the press that Yanukovich also agreed to the idea of organizing completely new presidential elections.