PITTSBURGH, September 25 (RIA Novosti) - Russian President Dmitry Medvedev says there has been a deterioration in Russian-Ukrainian relations, but does not want to exaggerate the differences between the two neighbors.

"It is not fatal," Medvedev told a gathering at the University of Pittsburgh on Thursday.

"The goal of the leadership of our countries, the future leadership of Ukrainian and the future leadership of Russia, is to do our best in order to make our relationship less problematic, but based on mutual advantage and, at the same time, on the special sympathy that has always existed between our countries," he said.

He said the Ukrainian side, including the president, had not done enough to develop bilateral relations between Russia and Ukraine.

"Just the opposite, it seemed that these ties were often replaced by schemes, not developed in any way that would be in the interest of the people," Russian President said.

Medvedev added that he had expressed these ideas in an open letter to the Ukrainian president in August, but Viktor Yushchenko did not agree with him.

In the August 11 letter, Medvedev blamed Kiev for the deterioration in relations between the two former Soviet republics, strained in recent years by gas disputes, Ukraine's desire to join NATO, and interpretations of the Soviet-era famine in Ukraine. Russia has also accused Ukraine of supplying weapons to Georgia during last year's war between Russia and Georgia over South Ossetia.

Yushchenko said in response to the letter that he was "very disappointed" by its "unfriendly nature." He agreed Russian-Ukrainian ties faced major problems and criticized Medvedev for excluding any possibility that Russia was responsible.

Medvedev has since said he sees no possibility to improve bilateral relations between the two countries while Yushchenko remains president.

Presidential elections in Ukraine are scheduled for January 17, 2010.