The move came despite the United People's Freedom Alliance (UPFA) suffering a sharp decline in a local election held at the weekend that was seen as a gauge for presidential polls.
Economic Development Minister Basil Rajapakse inaugurated an "Operations Centre" to lead his brother President Mahinda Rajapakse's bid for a third term in office, the sources said.
"Basil cut a blue ribbon (the colour of the party) to launch the office at the astrologically auspicious time of 10:01 am (1001 IST) and commence work," a party official at the ceremony told AFP.
The UPFA saw its vote plummet by over 20 percentage points in elections on Saturday for the Uva Provincial council in which the main opposition United National Party (UNP) more than doubled its vote.
It was the party's worst performance since Rajapakse came to power in 2005.
"The feeling is that the longer you delay, the worse it will get for the president," a senior UPFA source told AFP, adding that the presidential election was "most likely to be held in the second week of January."
The Roman Catholic Church in Sri Lanka has asked all politicians not to use the papal visit as a political tool in their campaigning to secure votes from the 7.5 per cent of the population that is Christian.
Last week, UPFA politician Dayasiri Jayasekera accused unnamed foreign governments of trying to engineer "regime change" by supporting the UNP.
President Rajapakse, who is currently in New York attending the UN General Assembly, is under intense international pressure to probe allegations that his troops killed up to 40,000 ethnic Tamil civilians while battling Tamil rebels in 2009.
