He pointed out that a free trade agreement (FTA) to be reached between the two countries will bring about more opportunities for bilateral cooperation.
"With the advent of FTA, Switzerland will become the first country in continental Europe and the first of the world's top 20 economies to reach an FTA with China, the implications of which will be significant," Li wrote.
Switzerland is one of the first European countries to recognize China's market economy status and initiated FTA talks with Beijing.
The negotiations have made substantial progress after nine rounds of talks.
China is now Switzerland's largest trade partner in Asia, while Switzerland is China's seventh largest trade partner and the sixth largest source of foreign investment in Europe.
Statistics showed that two-way trade exceeded 30 billion U.S. dollars in 2011, a record 50 percent increase compared to that of 2010.
Despite the sovereign debt crisis in Europe and uncertainties in world economy, bilateral trade between China and Switzerland remained as high as 26.3 billion U.S. dollars last year.
Switzerland is the third leg of Li's four-country tour, which has taken him to India and Pakistan. The last stop is Germany.
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