The European Union imposed wide-ranging economic sanctions on Belarus for the first time yesterday, targeting its main export industries and access to finance a month after it forced a Ryanair flight to land in Minsk.

The measures include banning EU businesses from importing goods or doing business with Belarusian companies in sectors including banking, petroleum products and potash, a salt used in fertiliser that is the country's main export.

The sanctions are far stricter than measures imposed in the past, which mainly consisted of blacklists of Belarusian officials and had little or no impact on the behaviour of President Alexander Lukashenko, in power since 1994.

The most significant measure for the Belarusian economy is the ban on EU companies from transporting potash. Belarus will now need to find other countries and ports to ship its top export via the Baltic Sea.

Russian President Vladimir Putin is Mr Lukashenko's closest ally but Russia does not have enough port capacity to handle Belarusian fertilisers or its own, data showed.

EU leaders were outraged by the interception of the Ryanair plane flying between Athens and Vilnius on 23 May. Belarusian authorities arrested a dissident journalist and his girlfriend after the plane landed, in an incident which Western countries branded state piracy. Mr Lukashenko said the interception was justified to prevent a rebellion in Belarus.

Diplomats said the decision to impose harsher sanctions was taken unusually quickly, reflecting the seriousness with which governments viewed the Ryanair incident.

The EU has also banned overflights of Belarusian territory by its airlines and banished Belarusian carriers from its air space.

The EU, the United States, Britain and Canada also expanded blacklists this week, with the EU now banning 166 people from travelling or doing business in the bloc, including Russian businessman Mikhail Gutseriyev, Belarus's largest foreign investor.