Putin, who has ruled Russia for eight years, said he will take over as prime minister after his successor, Dmitry Medvedev, is sworn in as president on May 7. Russia's State Duma is set to approve Putin's candidacy as premier on May 8.
"If Vladimir Putin heads the United Russia party, it would be the very best option," Boris Gryzlov, the leader of the United Russia party, and the speaker Russia's lower house of parliament, told a news conference last week.
It is widely expected that the proposal to head the United Russia party will be made to Putin on Tuesday. President-elect Medvedev, who is to attend the conference, has also been invited to join the party.
The party conference, which starts Monday afternoon, will gather around 600 delegates from the regions, over 1,500 guests and 800 Russian and foreign journalists.
On Monday, the pro-Kremlin United Russia party is expected to discuss the country's development strategy up to 2020.
At a United Russia party conference last year Putin said he would become prime minister in 2008, if the United Russia party won the December 2007 parliamentary elections, and an 'efficient person' was elected to the post of Russian president.
United Russia, whose candidate list was headed by President Putin, won a landslide victory with 64.3% of the vote.
