The Swiss foreign ministry has intervened with Turkey over a boycott of trainer aircraft from the Pilatus company of Stans in central Switzerland.
The move follows a decision by Ankara barring Pilatus from putting in a bid to supply the PC-21 turbo trainer to the Turkish Air Force.
A Pilatus spokesman confirmed to swissinfo earlier this month that the Turkish authorities had forbidden the company from tendering for a contract.
"The foreign ministry is informed about this matter. We have addressed the Pilatus case at the diplomatic level both in Bern and Turkey," ministry spokeswoman Carine Carey told swissinfo.
She added that the ministry would follow the matter closely.
Economics Minister Joseph Deiss has offered to try to find a solution to the problem during a visit to Turkey, which has long been on the cards.
However, the two countries have still not agreed on a date after a planned visit last September was postponed.
News of the boycott came in a letter sent to Pilatus from the Turkish defence ministry.
The Turkish Daily News reported a week ago that Pilatus had been excluded from bidding for the $500 million (SFr634.4 million) contract because of a diplomatic row between the two countries.
It quoted a defence official as saying he did not think Swiss contenders would be reliable partners in defence contracts.
Bilateral relations have been strained, particularly since 2003 when the Swiss House of Representatives recognised the "genocide" of Armenians at the time of the First World War.
However, the Swiss government does not officially speak of "genocide" but of "mass deportation" and "massacre".
The chief executive of Pilatus, Oscar Schwenk, told the Tages-Anzeiger it was the first time in the company's history that the company was not allowed to bid for a deal for which it was highly qualified.
The company has been talking to Turkish authorities and companies for four years about the supply of aircraft.
In the meantime, Turkey has been in contact with other companies, including Embraer of Brazil, South Korea's Aerospace Industries and Raytheon of the United States.
"As an enterprise we can do nothing; only Bern can unblock the issue," Schwenk commented.
swissinfo with agencies
Pilatus is the world market leader in the manufacture of single-engine turboprop aircraft and the only Swiss company to develop, produce and sell aircraft and training systems all over the world.
The company launched the development of a completely new training system, the PC-21, in 1999.
The aim was to meet the expectations of modern air forces over the next 30 years both in terms of capability and life-cycle cost.
The historical interpretation of the deaths or deportations of between 800,000 and 1.8 million Armenians between 1915 and 1919 has caused tensions between Turkey and many European countries.
The killings have been recognised as genocide by the parliaments of several countries, including France, Russia and Italy.
Switzerland's House of Representatives followed suit in 2003, but the Senate has not discussed the issue.
The Swiss government does not officially speak of "genocide", but of "mass deportation" and "massacre".
Relations have also been strained outside politics, particularly after Switzerland qualified for this year's World Cup soccer championships in a controversial match in Istanbul last November.
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