John Kerry talks tough ahead of meeting with Russian foreign minister

Secretary of State John Kerry warned that there would be "a very serious series of responses on Monday" from both Europe and the United States on Monday if a planned referendum on Crimean independence goes forward over the weekend.

Kerry, who was testifying on the State Department budget before the Senate Appropriations Committee's Foreign Operations Subcommittee, will meet with Russian Foreign Minister Sergei Lavrov in London on Friday in another attempt to resolve the crisis in Ukraine. The clock is ticking down to the March 16 referendum, which the United States views as illegitimate under Ukrainian law.

Kerry will continue his efforts to find a diplomatic resolution to the crisis ahead of the referendum, but isn't backing off his threat of sanctions should no resolution be reached. The U.S. has already created a list of individuals who might face sanctions if the current standoff continues, he said.

"The question is whether Russia is prepared to negotiate with Ukraine to resolve this in a way that respects their interests, but in a way that doesn't violate international law," Kerry said at the hearing.

Russian forces amassed on the border with Ukraine Thursday, which Ukraine's acting president Oleksandr Turchynov indicated was a sign they were"ready to invade."

Kerry said that the U.S. was closely monitoring troop movements while trying "not to create hysteria or excessive concern." Although Russian forces in the Crimean Peninsula have violated their basing agreement by interfering in Ukraine's sovereignty, he said, the estimated number of troops there is still believed to be under the 25,000 limit.

"They don't have the assets in place to march in and take over all of Ukraine, but that could change any minute," he said.

Both Kerry and Defense Secretary Chuck Hagel, who appeared at a separate hearing, urged Congress to approve a set of 2010 reforms to the International Monetary Fund (IMF) that would make funds more readily available and expand the power of some emerging countries.

"The IMF is best positioned to provide Ukrainian government and people with the technical expertise and the financial resources it needs," Hagel said. Kerry argued that failing to pass the reforms would be "sending a message that we're not prepared to lead."

But House leaders have remained adamant that the IMF reforms are unnecessary to move ahead with an aid package for Ukraine like the one the House passed earlier this week.

"The IMF money has nothing to do with Ukraine. I understand the administration wants the IMF money. But it has nothing at all to do with Ukraine. So let's just understand what the facts are here," Boehner told reporters Thursday.

Although Congress has been largely unified in a desire to help Ukraine and punish Russian actions, the IMF issue could prevent any legislation from passing until the last week of March since lawmakers have a recess next week.

Senate Majority Leader Harry Reid, D-Nev., said the IMF reforms have "everything to do with Ukraine." He also criticized the House bill for failing to authorize any sanctions against Russia (the House passed a nonbinding resolution condemning Russian violation of Ukrainian sovereignty).

The Senate bill that authorizes a loan guarantee to Ukraine includes both IMF reforms and preparation for further sanctions against Ukrainians and Russians who were involved with the violent response to Ukrainian protestors and Russian officials who were complicit or responsible for corruption in Ukraine.