The army and the rebels are observing a ceasefire
"The PA supports all measures taken by the government to get the proposed peace talks moving," former Foreign Minister Lakshman Kadirgamar told parliament on Wednesday.
Analysts say, however, that while the PA does not want to be seen undermining the peace process, it is prepared to be critical of the government should the process collapse.
The move comes the day after Prime Minister Ranil Wickramasinghe said he was considering lifting a ban on the Tigers in an effort to end the 18-year-old conflict.
The Tigers, who are fighting for a separate homeland in Sri Lanka, are refusing to enter direct talks with the government unless they are legalised.
Ceasefire conclusion
During last year's parliamentary election campaign, the PA, then holding power in parliament, accused Mr Wickramasinghe of selling out to the Tamil Tigers.
Both sides began ceasefires shortly after Mr Wickramasinghe took office.
Last week Mrs Kumaratunga cautioned the government over the rebels' sincerity in wanting peace.
Mrs Kumaratunga is still president and could play an influential role in determining the success of any peace deal.
Peace push
Mr Wickramasinghe won December's parliamentary elections on a pledge to restore the peace process.
Since becoming prime minister, he has eased an economic embargo on rebel-held areas in the north.
Norway has also resumed its mediation role.
The rebels' insistence that they be legalised is the first new obstacle to emerge for a resumption of direct talks between the two sides.
The rebels on Tuesday said they hope to open the main highway to the northern town of Jaffna soon.
Negotiations are under way to open the route initially into Tiger-controlled territory and then in a second stage along the strategic Elephant Pass.
The steps are part of confidence building measures taken by both sides.