The National Conference will be a part of the ruling United Progressive Alliance (UPA) and the Congress is likely to contest the next elections with a pre-poll alliance with the party.
The decision comes after the Congress decided to extend support to NC led by Omar Abdullah in forming the next government in Jammu and Kashmir.
"It is almost certain that we will enter into a pre-poll alliance with the NC. The modalities will be worked out soon," a senior party leader said, on condition of anonymity.
He said that the PDP would continue to be a part of the UPA and talked of "coopting" the party in central government but was not clear how the process will be worked out.
"In the past we have had examples where two state parties, who are otherwise rivals, have supported the UPA. We do not see any problem on that count," the senior leader said.
Sources in the Congress revealed that the party had an "open offer" from the PDP to form the next government in the state.
"We consciously decided to spurn the offer as it was against the mandate of the people and stability," the sources said.
On the different perceptions of the Congress and the NC on a host of issues, the leader said that there are two agendas - developmental and political - of both the parties.
"The developmental agenda of both the parties is almost similar. We will take it forward. But on the political agenda, we will sit together and work out the best possible scenario to be implemented," he said.