Moscow (AFP) - The Russian ruble slumped to another record low against the dollar on Thursday as the European Union prepared to hit Moscow with harsher sanctions over the Ukraine crisis.

The ruble weakened to 37.57 against the dollar at about 1135 GMT, a new record after hitting 37.51 on September 1.

The ruble also weakened against the euro to 48.50 rubles, but stayed above the five-month low of 49.0903 hit at the start of the month.

The Moscow stock markets fell, with the ruble-denominated Micex down 0.33 percent and the dollar-denominated RTS down 0.86 percent.

The European Union on Friday will impose new sanctions on Russia that will likely limit access to financial markets for Russian oil companies such as Rosneft and Transneft and the petroleum unit of gas giant Gazprom.

Brussels is also set to add several dozen names to its blacklist who will face asset freezes and travel bans.

The increasingly severe sanctions over Russia's alleged support for separatists in eastern Ukraine have already provoked massive capital flight and left the country on the verge of recession.

Russia has responded by banning most food imports from countries that have imposed sanctions and has threatened further reprisals to the new measures.