The European Parliament has ratified seven key accords between the European Union and Switzerland. The agreements cover a range of issues, including agriculture, transport and the free movement of people.
The accords were approved without any opposition during a session of the parliament in Brussels on Thursday.
Addressing the assembly, the EU's foreign affairs commissioner, Chris Patten, said the treaties were a milestone in relations with Switzerland.
"The agreements are very important. They do unblock the stalemate in the relations with one of our closest neighbours and our second biggest trading partner," he said.
The accords took about five years to negotiate, after the Swiss people rejected membership of the European Economic Area in 1992. They will bring Switzerland closer to the European Union than it has ever been before.
Switzerland immediately welcomed the European Parliament's vote.
"It shows that Switzerland's partners in the EU support the bilateral treaties," said the president, Adolf Ogi. "The government is pleased, and I think it also shows understanding on the part of the EU for the path chosen by Switzerland in Europe."
Brussels correspondent, Regula Schmid, said the ratification by the European Parliament was seen by deputies as the best possible solution to the question of Switzerland's relationship to the EU.
"Everyone understands that having Switzerland in the middle of Europe being isolated, is just no way forward. So, having noticed that Switzerland does not want to become a member yet, the only way out was the bilateral agreements and they have been negotiated for so long, that there is no opposition left. "
One senior leader of the European Parliament, Massimo Carraro, said ratification would give a clear vote of confidence ahead of a referendum on the accords in Switzerland on May 21.
The referendum is the next in a long series of hurdles for the accords. The deal on the free movement of people still has to be ratified by the parliaments of all 15 EU member states. Only then can the seven treaties come into law.
Some EU countries, including Spain, Portugal and Italy, have criticised what they consider Switzerland's delay in cementing relations with the EU.
swissinfo with agencies