The source said the PACE mission will be led by Switzerland's Andreas Gross, formerly the organization's rapporteur on the troubled North Caucasus republic of Chechnya.
Another PACE source said that elections themselves would be monitored by a team of 30 members of the organization.
The Organization for Security and Cooperation in Europe (OSCE) on Tuesday asked Russia's Central Election Commission for authorization to monitor not only the presidential election, but also campaign leading up to the polls.
The OSCE'S main election monitoring arm, the ODIHR, boycotted Russia's parliamentary polls on December 2 citing visa delays and "unprecedented restrictions." The OSCE subsequently declared the polls "not free and fair."
President Vladimir Putin said on Wednesday that Russia will not allow foreign countries to influence its presidential election, due on March 2.
Speaking at a session of the country's main domestic security service, the FSB, Putin urged for measures to deter "attempts to interfere in Russia's domestic affairs."
"It is especially important in the run-up to the presidential election. Russia is a sovereign state, and we will not allow anyone to influence the election campaign from the outside."