The European Union
The officials held responsible for "undermining Ukraine's territorial integrity, sovereignty and independence" will be banned from traveling to the 28-nation bloc and will see their assets there frozen, the EU said in a statement.
The decision taken by the EU governments' ambassadors in Brussels brings the total number of Russians or pro-Russian individuals in Ukraine targeted by the EU's sanctions to 48.
The EU's European Commission is drawing up a list of tougher economic sanctions that could be imposed on Russia, but the EU is split between countries in favor of stronger action, including Britain, France, Poland, Sweden, Denmark, the Czech Republic and the Baltic countries, and those who are reluctant, such as Italy, Greece, Cyprus, Bulgaria, Hungary, Luxembourg, Austria, Spain, Portugal and Malta.
Obama said the measures do not yet include the wider sanctions, such as curbs on the Russian financial and energy sectors, that would do the most serious damage to Russia's economy.
“We are keeping in reserve additional steps that we could take should the situation escalate further,” Obama said, acknowledging that he did not know if the measures he has ordered so far will work.
Many Europeans oppose sanctions that would target the economy, because economic sanctions would hurt European economies as well as that of Russia.
The U.S., being economically tied with Russia to a much lesser degree than Europe, says it would not impose economic sanctions unilaterally.
However, European leaders were giving more consideration to broad sanctions against sectors of the Russian economy after pro-Russian rebels in eastern Ukraine held seven monitors from the Organization for Security and Cooperation in Europe (OSCE), a U.S. official said Monday.
"We have noticed a distinct uptick in the last three days from major European capitals in continuing to look very hard at sectoral [sanctions] in response to the egregious treatment of the ... monitors in Slovyansk,'' a U.S. official said.
The OSCE had sent unarmed monitors to try to encourage compliance with a peace deal. The rebels seized them and have been holding them at a fortified redoubt in the town of Slovyansk.
Nevertheless, such measures have done nothing so far to deter Putin, who overturned decades of post-Cold War diplomacy last month to seize and annex Ukraine's Crimea peninsula and has since massed tens of thousands of troops on the frontier.
He acted after Ukraine's pro-Russian president was ousted in February by protesters demanding closer links with Europe.
At a meeting of eastern Ukrainian leaders and acting Prime Minister Arseniy Yatsenyuk earlier this month, Kernes insisted he does not support the pro-Russia insurgents and backed a united Ukraine.
Obama is under pressure from opposition Republicans at home to move faster on sanctions. But in taking what he described as “calibrated steps”, he has emphasized the need to act in concert with European countries, which have more at stake economically and a more cumbersome process for taking decisions.
The EU does more than 10 times as much trade with Russia as the U.S. and buys a quarter of its natural gas from Moscow. Most EU decisions require unanimity among member states.
Western countries say the targeted sanctions are already having an effect on Russia by scaring investors into pulling out capital. The central bank has been forced to raise interest rates to prop up the rouble and Russian firms are finding it more difficult and costly to raise funds.