Ukrainian president Viktor Yanukovich is to meet his Russiian counterpart Vladimir Putin at the Kremlin, in a bid to plug the country's $17bn funding gap.
The meeting aims to discuss closer operations with Russia, after Mr Yanukovich spurned a trade and investment deal with the European Union last month.
The agenda will be dominated by discussions about a loan, as well as a discount on Russian natural gas.
Ukraine requires urgent financial assistance to keep the economy stable, as the country attempts to cover its vast funding gap.
Ahead of the meeting, Ukrainian Prime Minister Mykola Azarov said he hoped a deal on cheaper gas prices would soon be concluded. A reduction of at least 10-15% is likely, according to sources in Kiev.
Mr Yanukovich's U-turn on the EU association deal sparked protests in Ukraine where demonstrators have been camped out since late November, in the biggest anti-government protest since the 2004 Orange revolution.
While Moscow wants Kiev to join the Customs Union instead of signing the EU pact, Ukraine protesters demand a free trade pact with the EU.
Opposition leader Arseniy Yatsenyuk told the BBC: "If the (Customs Union) agreement is signed, he (Mr Yanukovich) can remain in Moscow and not return to Kiev. I'm sure that the visit is wrong and nobody knows the conditions of these negotiations."
This sentiment is common among the protesters, who want to loosen historic ties to Russia in favor of integration with Europe.
The UK foreign secretary William Hague has sent a message of support to demonstrators in Ukraine, telling them he shares their vision of closer ties with the European Union.
"The EU door remains open to Ukraine, but clearly they are not willing or able to walk through it," Mr Hague told reporters in Brussels. "Ukraine should be able to decide on these things without external pressure."