WASHINGTON (AP) -- Capping a week of aggressive action against Russia, President Barack Obama pressed Russian President Vladimir Putin Friday for a diplomatic path out of Ukraine's struggle with Moscow-backed pro-Russian separatists. Putin countered by calling U.S. and European economic sanctions against Russia counterproductive.
Obama later conceded that pressure from recently imposed U.S. and European measures to squeeze the Russian economy "hasn't resolved the problem yet."
In an Obama-initiated phone call Friday, the U.S. president also raised concerns that Russia violated a key Cold War era nuclear weapons treaty, the White House said. In a letter this week from Obama to Putin and in an administration report released this week, the United States said Russia violated a 1987 treaty that bans all U.S. and Russian missiles of intermediate range, meaning those that can travel between about 300 miles and about 3,400 miles.
Putin in the call said the sanctions seriously damage bilateral cooperation and general global stability, according to a Kremlin report on the call.
It was the first conversation between the leaders since the U.S. and Europe slapped the new round of economic sanctions on Russia and since Obama's letter claiming a breach in the missile treaty.
"I indicated to him, just as we will do what we say we do in terms of sanctions, we'll also do what we say in terms of wanting to resolve this issue diplomatically if he takes a different position," Obama told reporters later.
The Kremlin said both Obama and Putin underscored the urgency for bringing an end to fighting in eastern Ukraine and spoke positively about a meeting that took place the day before in Minsk, Belarus, among members of a diplomatic "contact group" pursuing an end to hostilities. That group includes representatives from Russia, Ukraine and the Organization for Security and Cooperation in Europe.
"If he respects and honors the right of Ukrainians to determine their own destiny," Obama said in an afternoon news conference, "then it's possible to make sure that Russian interests are addressed that are legitimate and that Ukrainians are able to make their own decisions, and we can resolve this conflict and end some of the bloodshed."
In a lengthy statement devoted to the Intermediate-Range Nuclear Forces Treaty, the Russian Foreign Ministry criticized the U.S. report that included the allegation that Russia had violated the pact that President Ronald Reagan signed with Soviet leader Mikhail Gorbachev.
"The claims are put forward practically without evidence, based on strange deductions and suppositions," the statement said.
The Obama-Putin call came as the U.S. was poised to send an additional $27 million in military aid to Ukraine in an effort to strengthen the struggling nation's national guard and beef up its ability to protect its border. The money comes amid increased congressional pressure on the administration to increase support for Ukraine as it battles Russian-backed separatists.
U.S. officials said the aid includes $19 million for the Ukrainian National Guard and $8 million for border security, including surveillance equipment, armored vehicles, and small boats.
On Thursday, five Republican senators sent Obama a letter calling on the president to supply Ukraine with weapons and not just non-lethal assistance.
"A failure to provide appropriate lethal assistance to Ukraine would lead Putin to conclude that the West is not willing to stand against his aggression and clear violations of international law," said the letter signed by Sens. Kelly Ayotte of New Hampshire, James Inhofe of Oklahoma, John McCain of Arizona, Marco Rubio of Florida and Lindsey Graham of South Carolina.
At least 12,000 Russian troops are gathered close to Ukraine's eastern border. The U.S. has complained about Moscow sending heavy military equipment across the border to support the separatists, including surface-to-air missile systems that officials say were likely used to shoot down a Malaysian Airlines flight.
Also Friday, Vice President Joe Biden called Ukrainian President Petro Poroshenko to announce the border assistance and to discuss the "increasing prevalence" of artillery and rocket fire into Ukraine from Russia, the White House said.
According to the White House, Poroshenko did say that access to the site of last month's Malaysian airline crash that killed nearly 300 people had been secured despite continued fighting in the vicinity. The crash, which the West has blamed on separatists using Russian-made missiles, is the subject of an international investigation.
Associated Press writers Lolita C. Baldor and Josh Lederman in Washington and Jim Heintz in Moscow contributed to this article.
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