When German Chancellor Angela Merkel meets with President Obama at the White House Monday, there is one big point of contention they are expected to discuss: whether the United States and Europe should give lethal aide to the Ukrainian military as it looks to defeat pro-Russian separatist militias in the eastern part of the country.

Mr. Obama previously opposed such a move, but is reportedly reconsidering his stance in light of increasing violence in eastern Ukraine. Merkel, however, said last week it was her "firm belief" the conflict will not be solved militarily.

Tom Donilon, the president's former national security adviser, said on "Face the Nation" Sunday that while he is in favor of arming the Ukrainians, the "sequencing" of decisions will be important.

"One of the reasons, I think, that you had this latest effort to go to Moscow and try to get a political solution is because of the prospect of arming the Ukrainians. So my view would be engage in the politics. Engage in the diplomacy. But hold back here as the next step that you take, increasing the cost for the provision of arms," he said.

Donilon said Russia has violated the provisions of a peace plan brokered last fall and has given no indication they will stop supporting the pro-Russian separatists in Ukraine. But, he said, "maybe this latest round of politics and maybe the threat of having us arm the Ukrainians may change the dynamic. We'll see tomorrow."

CBS News Senior National Security Contributor Michael Morell, the former deputy CIA director, said the U.S. should also be reaching out publicly to the Russian people.

"The real loser is Russia. It's the Russian economy. It's the Russian middle class. Because of what [Russian President Vladimir] Putin has done here, any hope of integrating Russia with the West is gone. So Russia's the big loser," Morell said. "We should talk to the Russians. And we should talk to the Russian people publicly about that."