As before, Swiss President Alain Berset has reiterated that his country opposes exporting weapons to war-torn Ukraine.

Switzerland bars the re-export of Swiss weaponry to nations at war, but the issue of the country's long tradition of neutrality has been under debate since Russia's full-scale invasion of Ukraine just over a year ago.

"The discussion about the export of arms, weapons... while we have (our) legal framework in Switzerland, it is not possible to do it," AFP quoted Berset, who currently holds the country's rotating one-year presidency.

"For the government and for the Federal Council, we have to, and we want to, maintain this legal framework and to work in this legal framework," he said.

His comments came after Berlin requested in late February that German arms manufacturer Rheinmetall be permitted to acquire old Swiss Leopard tanks, guaranteeing they will not be transferred to Ukraine.

While the wealthy Alpine country, which is not a member of the European Union, has followed the bloc's lead on sanctions targeting Moscow, it has so far shown less flexibility on its military neutrality.

"These sanctions, they are absolutely compatible with the neutrality," Berset said.

Despite pressure from Kyiv and its allies, Switzerland has so far refused to allow countries that hold Swiss-made weaponry to re-export it to war-ravaged Ukraine, and has to date rejected explicit requests from Germany, Spain and Denmark.

Several initiatives are under way in parliament towards relaxing the re-export rules, but any decision is likely months away.

Berset, who met in New York with UN chief António Guterres just before the Secretary-General travelled to Ukraine, noted that the Swiss parliament "has a lot of possibilities to change the laws".

"If the parliament would agree to change this legal framework, then we will work in the context of this new legal framework, but we will also take time," he said.

But, he emphasised, "It's not possible to make exceptions to the legal framework."

On 6 March, the Council of Cantons (the upper house of the Swiss parliament) rejected a request to allow the re-export of weapons after several hours of debate, which would provide for the provision of Swiss-made weapons to Ukraine.

At the same time, the issue of re-exporting weapons will also be on the agenda of the National Council (the lower house) during the current session. A discussion of the Security Policy Committee's proposal, which was made back in January, is expected next Wednesday.