Viktor Yushchenko, whose order to dissolve parliament controlled by factions loyal to his long-time rival, Prime Minister Viktor Yanukovych, triggered a new wave of tensions with the defiant legislature, earlier refused outside assistance, saying the conflict was Ukraine's domestic affair.
"As for third parties being involved in the settlement, I would like to say I am not ruling out the possibility," Yushchenko said and also thanked the countries that had offered assistance.
A group of Russian lawmakers, a Lithuanian government delegation, European Parliament members and Poland's ex-president are now in Ukraine meeting with factions in the conflict after being invited by the coalition.
Ex-President Aleksander Kwasniewski mediated during Ukraine's "orange revolution" in 2004, when the Western-leaning Yushchenko defeated Yanukovych backed by Moscow in a rerun of an allegedly rigged presidential election.
European Parliament Vice President Marek Siwiec said Thursday the European Union should change its attitude to what was happening in Ukraine, since further escalation in the crisis could threaten European interests and Ukraine's European ambitions.
Adrian Severin, head of the European Parliament delegation for liaisons with Ukraine, proposed a hearing on the crisis in Brussels to help the sides start dialogue.
Yushchenko said "a format for international aid" should be coordinated by all parties to the conflict after "the legal aspect" had been settled in a reference to the Constitutional Court, which is due to begin examining the case April 17.
Yushchenko said Russian lawmakers' assessment that his decision was "unconstitutional" and a "threat to democracy" was too emotional and did not reflect Moscow's position.
Russia's Foreign Minister Sergei Lavrov earlier called on its former Soviet ally for calm and expressed readiness to help if Kiev requested aid.
Yushchenko refused Thursday to meet Yanukovych's demands to backtrack on his decree and said there were no legal grounds to call an early presidential poll in parallel, but he said elections, originally slated for May 27, could be postponed until a later date.
Thousands of coalition supporters and several hundred pro-presidential backers have been meanwhile facing off on the streets of the capital, Kiev.
