The rightwing Swiss People's Party has threatened to withdraw its support from Samuel Schmid, one of its two representatives in government.
The People's Party president, Ueli Maurer, has harshly criticised Schmid's suggestion that cabinet ministers should distance themselves from their parties.
Speaking in the Sunday newspaper, SonntagsZeitung, Maurer said it was the duty of government ministers to remain loyal to their parties.
If Schmid, Maurer warned, refused to represent the core values of the party going into the 2007 cabinet election, his "renomination would not be conceivable".
He said ministers were elected to the government as representatives of their parties and therefore had a responsibility to try and implement party policies.
Maurer was responding to comments Schmid made in an interview published on Saturday by the Berner Zeitung and Neue Luzerner Zeitung newspapers.
"One should contemplate whether when taking up his post a government minister should resign from his party in order to underline his independence," said Schmid.
Schmid was referring to cabinet ministers who in recent weeks have taken to publicly criticising each other, breaking the unwritten code of Switzerland's consensus form of decision-making.
Members of the executive are expected to represent the policies of the majority, which are not necessarily in line with their own or their party's views.
Schmid charged some of his colleagues with a "lack of self-discipline and loyalty [to the cabinet]," accusing them of "using the media to advance party politics".
Earlier this week, the justice minister, Christoph Blocher, also of the People's Party, criticised the policies of the Social Democratic transport minister, Moritz Leuenberger.
Blocher denounced the introduction of tougher drinking and driving laws and described efforts to enforce speed limits as "chicanery".
Leuenberger responded by saying Blocher was guilty of "simplifying matters" and acting "irresponsibly".
Schmid said this type of politicking endangered the consensus style of government that was crucial for the stability of the country.
The latest dispute between Schmid and his party comes only a couple of weeks after the defence minister refused to support a call from his party for the formal withdrawal of Switzerland's application for European Union membership.
The request was made in 1992 but frozen the same year in the wake of voters' rejection of the European Economic Area treaty.
swissinfo with agencies
Executive power is vested in the seven-member cabinet, made up of representatives from the four largest parties.
Members are elected, re-elected or extremely rarely dismissed by parliament in Bern every four years.
It is not uncommon for cabinet members or ministers to stay in office for ten years or more, although most change portfolios during that time.
Samuel Schmid is the defence and sport minister, and this year's Swiss president.
The largely ceremonial post of president is a one-year term, which is rotated among cabinet ministers.