The Sri Lanka Freedom Party (SLFP) and the Sri Lanka Podujana Peramuna (SLPP) have decided to continue talks despite differences of opinion.
Both sides met today and discussed working together at the next election.
They later agreed to meet again for more talks on June 17.
The SLFP was represented at the talks today by SLFP General Secretary Dayasiri Jayasekara, MP Thilanga Sumathipala and Professor Rohana Lakshman Piyadasa.
The SLPP was represented by Professor G.L. Peiris and MP Dullas Alahapperuma.
Both sides have already held several rounds of talks but have failed to reach a final agreement.