WASHINGTON U.S. Senators John McCain, a leading Republican voice on foreign policy issues, and Chris Murphy, the Democratic chairman of the Senate's Europe subcommittee, will visit the Ukrainian capital on Sunday, the day the Ukrainian opposition plans a mass rally, aides said on Friday.
Also on Friday, senators issued a resolution calling for the United States to consider sanctions in case there is further violence against peaceful demonstrators.
"Senator Murphy will join Senator McCain in Kiev to meet with Ukrainian officials, opposition leaders and civil society leaders," said Ben Marter, a spokesman for Murphy.
U.S. Democrats and Republicans have condemned the Kiev government's occasional harsh measures during weeks of protests by hundreds of thousands of people over President Viktor Yanukovich's decision to scrap a trade deal with the European Union and steer Ukraine closer to Russia.
In his first direct attempt to defuse weeks of unrest, Yanukovich made few concessions in crisis talks with the opposition on Friday as protesters streamed into Kiev ahead of Sunday's rally.
U.S. Republican and Democratic senators introduced a resolution calling for a "peaceful and democratic conclusion" to the Ukraine crisis that would allow Ukraine to become an active member of the European community.
"Ukrainians are protesting in the streets today because they know they're being sold out by their government for short-term monetary gain from Russia, and they rightly fear the long-term economic cost to Ukraine's economy," the backers of the resolution said in a statement.
The measure was sponsored by Murphy and Ron Johnson, the top Republican on the Europe subcommittee, as well as Democrats Jeanne Shaheen and Dick Durbin, who are also on the Senate Foreign Relations subcommittee.
The measure, which would be subject to approval by the Senate, said President Barack Obama's administration and the U.S. Congress should consider sanctions, including visa bans and assets freezes, against anyone responsible for the violence.
"This resolution makes clear that further violence by the government will have consequences for our bilateral relationship," the measure's sponsors said in a statement.
(Editing by Bob Burgdorfer)