One option Solidarity is considering seriously after the demonstrations in Poland Aug. 31 is the calling of a general strike throughout the country, a leader of the independent trade union said here Wednesday.
''The demonstrations revealed massive public support for Solidaryty,'' the head of the organization's foreign headquarters, Jerzy Milewski, said.
Mr. Milewski - one of the union's highest ranking officials, who happened to be outside Poland when martial law was declared last December - gave no details on a possible date for the strike. He said that secrecy until the last moment was crucial to the strike's success.
The official suggested that the call to strike would be followed by large segments of the Polish population.
''The Jaruzelski government has no support - even from the smallest groups in society,'' Milewski said.
The so-called ''coordinating office abroad'' of Solidarity was opened in Brussels on Sept. 1. Its main aim, according to a statement, ''is the creation of a bridge between Solidarity and trade unions abroad that would enable them to coordinate aid to our union still struggling for its basic rights in Poland.'' About 10 Solidarity members will work at the office here and at the branch office in Paris, organization officials said.