All foreign nationals need a visa to travel to the Russian Federation. You cannot enter Russia without a tourist, student or business visa. It is crucial that you follow the guidelines issued by the Russian Consulate in London. If your stay in Russia is to be longer than two to three days, your passport must be registered and stamped at the local office of the Ministry of Internal Affairs within one week of arrival.
Once you are in Russia, travelling out and in again may breach the conditions of your visa, which is one of the common frustrations experienced by expats living in the country. It is more common to apply for further permits while living in Russia.