Controversial former Justice Minister Christoph Blocher has criticised the current government as unable to defend the country's interests.
The strongman of the rightwing Swiss People's Party told swissinfo.ch that the cabinet lacked a strong personality who is able to stand his ground against pressure from abroad.
He calls for a prominent financial expert to replace Interior Minister Pascal Couchepin. Parliament is to choose a new member for the multi-party government on September 16.
Blocher served in the cabinet four years before he was unseated in the wake of the 2007 general elections.
The billionaire businessman is arguably one of the most divisive politicians of recent Swiss history.
He currently acts a strategic expert of his party, which won a record 28.9 per cent two years ago. His party holds one seat in the seven-strong cabinet.
swissinfo.ch: What kind of profile is required for someone who wants to succeed Couchepin in cabinet?
Christoph Blocher: A candidate has to stand fully behind Switzerland. There is incredible pressure on Switzerland right now and the government is caving in.
It is therefore crucial to include an economic expert in the cabinet who also knows the global financial system. This is what's missing at the moment.
swissinfo.ch: Are candidates with a traditional political career on local and cantonal levels not suited for the cabinet?
C.B.: I did not say that. But under the circumstances we recommend the Radical Party put forward somebody from outside the political scene.
Jean-Pierre Roth, the outgoing President of the National Bank, is an option. He has French mother tongue, and is not a member of a political party. He is respected by parliamentarians. The portfolios in the cabinet would have to be shared out accordingly.
I'm extremely concerned about the submissive attitude of the government against pressure from abroad. Switzerland is giving up its tax regulations and banking secrecy rules without demanding something from others.
swissinfo.ch: What happens if the Radicals refuse to put forward Roth?
C.B.: We will see. The People's Party is not willing to support just any candidate. Given our position as the largest party in parliament we are entitled to claim a second cabinet seat.
But I'm prepared to convince the People's Party that it supports a Radical Party candidate with the suitable qualifications. Otherwise we will present our own candidate.
swissinfo.ch: Are there any possible People's Party contenders from the French-language region of the country?
C.B.: Of course. We could also put forward Jean-Pierre Roth as an independent, non-partisan candidate. We don't mind asking him if the Radicals don't.
Besides there are excellent parliamentarians from our party. For instance Yves Nidegger from Geneva, Guy Parmelin from Vaud and Jean-François Rime, an entrepreneur from Fribourg.
Admittedly they do not have a political profile comparable with the president of the National Bank. I'm sure that Yves Nidegger, a lawyer with international experience, would learn quickly and be a competent cabinet minister.
swissinfo.ch: Your party appears to be more restrained in its reaction to the resignation of Couchepin than in similar cases of cabinet vacancies in the past. Why so moderate in setting the agenda?
C.B.: Everything in its own time. There is not only agenda setting. Sometimes it's better to wait.
Quite clearly the Christian Democratic Party which has never played fair, made a deal with the Social Democrats and the Greens for a majority centre-left government. The Christian Democrats are at the mercy of the left.
According to our own calculations a leftwing member of the Christian Democrats will be elected if we and the Radicals put forward separate candidates.
swissinfo.ch: Would the People's Party give its vote to a candidate of the Christian Democratic Party?
C.B.: They can go and ask Jean-Pierre Roth.
Seriously: We must put an end to the political scheming ahead of the cabinet election. The interests of the country are at stake and it is vital for Switzerland to defend its position.
The current cabinet is very weak in that respect.
swissinfo.ch: What about if Fulvio Pelli enters the race for the Radicals?
C.B.: I don't comment on names. The question is: Who has the necessary profile and can ensure that the government really defends the interests of the country.
swissinfo.ch: The operations of the UBS bank in the United States were not entirely above board, to say the least. What should the Swiss government have done about the legal action?
C.B.: There is no other way, but to punish those who acted illegally. But it is up to UBS and not the government.
Moreover a strategy is needed that allows banks to have foreign clients without breaking the law. For instance by introducing taxing at source for foreign investors.
It wouldn't be simple to impose such a policy because Americans will oppose it. There are apparently considerable funds in tax havens there.
Switzerland has to fight against the hypocrisy of the US using credible and strong arguments.
swissinfo.ch: What would you have done as a cabinet minister when Switzerland was blacklisted by the Organisation for Economic Co-operation and Development (OECD) last April?
C.B.: It is irrelevant if Switzerland is put on a black, grey, red or a white list. Also the OECD never decided on the list. It was the G20 group which did this.
Switzerland was a founding member of the OECD. The rules state that decisions can only be taken unanimously. But there is no such unanimous resolution.
Our rules of banking confidentiality have to be explained and defended by the government. Yet I don't see that happening. They say it is too complicated. But how else can other countries understand our banking rules if we don't even make the effort?
Andreas Keiser, swissinfo.ch (adapted from German by Urs Geiser)
The multi-party cabinet consists of four members of centre-right parties, as well as two members of the centre-left and one representative of the rightwing.
Interior Minister Pascal Couchepin of the centre-right Radical Party announced his resignation after more than 11 years in the cabinet.
Blocher, a billionaire businessman, is credited with making his rightwing Swiss People's Party the largest group in parliament, winning nearly 29% in the 2007 elections.
However, he failed to be re-elected amid controversy over his divisive political style.
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