A key guerrilla spokesman says he is ''fairly optimistic'' that negotiations to end the Salvadorean war will open by mid-1983.
Ruben Zamora, a member of the guerrillas' diplomatic-political committee, said that the insurgents did not take as definitive rejections by the Salvadorean government of their proposal to negotiate without preconditions.
''Our assessment is that we cannot take as definite the public rejection of negotiations,'' said Mr. Zamora in a telephone conversation. ''Privately, we continue to receive messages from both the civilian and military sides of the government saying, 'don't pay attention to what we say in public.'
''So we are fairly optimistic that by the middle of next year, negotiations will open.''
Zamora, secretary-general of the Popular Social Christian Movement (MPCC) added that he did not think US Secretary of State George P. Shultz had made any substantive changes so far in US policy toward El Salvador. He said that Mr. Shultz's approach seemed to be more cautious than that of his predecessor, Alexander M. Haig Jr.