The country will vote on whether to hold obligatory referendums each time the state enters into international treaties that are considered either to be important or to have financial implications for the people of Switzerland.
The initiative, launched by the Campaign for an Independent and Neutral Switzerland (AUNS), argues for more popular involvement in foreign policy decisions, and claims that the requirement for the electorate's support would give state negotiators more power, newspaper Tages Anzeiger reported.
The motion, supported predominantly by the far-right Swiss People’s Party, has caused concern among opponents, who fear that a positive result would lead to a costly administrative quagmire.
A majority of political parties and government ministers are opposed to the initiative.
Switzerland’s democratic system is world-famous, with some 12 referendums being held each year.
"In almost no other country in the world can the population vote on so many issues," Justice Minister Simonetta Sommaruga, who opposes the initiative, told a press conference.