Several administration officials said Sunday that the process of sanctioning Russian would take time to implement and could take even more time to garner a reaction from Russian president Vladimir Putin. The U.S. also wants to work with European Union countries to make sure the sanctions are coordinated for maximum effectiveness, while also preparing a multi-billion dollar economic aid package for the new leaders in Kiev.

The drive to find ways to tighten the economic noose around Putin’s neck is at the center of the administration’s strategy to not only punish Russian leaders but also to change their calculus about pushing forward with their occupation of Ukraine.

“We’re beginning to review all of our trade and economic cooperation with the Russian Federation,” a senior administration official told reporters on Sunday. “What we see here are distinctly 19th and 20th century decisions made by President Putin to address problems… but what he needs to understand that when it comes to the economy, he lives in a 21st century world, an interdependent world.”…

The view inside the Obama administration is that the White House can do a lot of the sanctions work on its own, without legislation from Congress, but that new Congressional legislation could be helpful, so long as it doesn’t contain a lot of items the administration is opposed to. For example, McCain also wants Obama to restore plans to build missile defense sites in Eastern Europe, which is not actually under consideration.