 Before joining the Christian Democrats, he had previously represented Moderate Party in the Riksdag 1991–1994, replacing Per Westerberg during his time as a minister.At the time of the Swedish 1994 referendum on membership in the European Union, Esch clashed with the Moderate Party as he campaigned on the "no" side.When he subsequently formed a list of EU critics that ran in the 1995 European Parliament election in Sweden, he was expelled from the party.