Swiss voters have swung to the right in parliamentary elections dominated by concerns over Europe's refugee crisis, with the country's largest party winning a record number of seats.

On Sunday, the populist Swiss People's Party (SVP), known for its virulent campaigns against immigration, the EU and Islam, won 65 of the 200 seats in the lower house, up from a current 54, and saw its support rise to its highest level ever.

The SVP raked in 29.4 percent of the vote, compared to the 26.6 percent it won in 2011 and beating its previous record of 28.9 percent in 2007, according to the Swiss media SRF. It was the best performance by a party in at least a century.

Along with advances made by the centre-right Liberal Party, Switzerland's third-largest party, which took three additional seats on top of its current 30, SVP's gains should tip the scale in parliament from the centre-left towards a centre-right majority.

The Socialists, the country's second-largest party, lost three of their 46 seats and the Greens and Green Liberal Party lost a total of nine seats.

Overall voter turnout was at 48 percent.

'Migration most important issue'

While Switzerland has not become a major destination for the thousands of refugees and migrants entering Europe each day, there has been a growing sense of unease about rising immigration in recent years.

Immigrants will make up half of Switzerland's population by 2030, the SVP warned in one of its campaign newsletters ahead of the elections.

About a quarter of Switzerland's eight million inhabitants are currently foreign nationals.

The latest survey from the gfs.bern polling institute before the election showed that 48 percent of those questioned thought migration was the most important issue facing the country.

Only nine percent chose the runner-up issue - Switzerland's relationship with the EU - as the most important.

Despite the shift to the right, the government will not look much different after the elections.

Switzerland's complex consensus-oriented political system is expected to prevent the SVP from taking over the government.

In contrast with other countries, cabinet posts are divided between the biggest parties according to a predefined ratio.

Source: Agencies