Joerg Meuthen and Alexander Gauland of the right-wing Alternative for Germany (AfD) | Alexander Koerner/Getty Images Germany’s AfD hit with hefty fine in donations scandal The German parliament considers free advertising received by party members illegal support.

The German parliament has imposed a hefty fine on the far-right Alternative for Germany (AfD) over "illegal" campaign donations from a Swiss-based company.

On Tuesday, the Bundestag's administrative body informed the AfD that it has to pay a €402,900 fine, following the parliament's verdict that free advertising received by two of the party's candidates constituted illegal party donations, according to German public broadcasters and news agencies.

AfD co-leader and MEP Jörg Meuthen and Guido Reil, an MEP candidate for the party, previously admitted to accepting undeclared campaign support from Goal AG, a public relations agency based in Switzerland. They used the agency's free advertising in regional election campaigns between 2016 and 2017.

The penalty orders, signed off by Bundestag President Wolfgang Schäuble, amount to three times the value of the free advertising, which was estimated at €89,800 for Meuthen and €44,500 for Reil.

The AfD said it would appeal against the fines and called the Bundestag's decision "politically motivated."

The Swiss campaign support for Meuthen and Reil is only one part of a larger donations scandal engulfing the AfD, which could face further fines.

The party's co-leader Alice Weidel is also under investigation for violating Germany's campaign finance laws. The AfD branch in Weidel's Lake Constance constituency has been accused of accepting large sums of money from a Swiss pharmaceutical company in the run-up to Germany's 2017 general election.

In Germany, it is illegal for parties to receive support from outside the European Union. Weidel's campaign returned the funds several months later, and the AfD said the Swiss company had transferred the money on behalf of EU citizens.

Yet German media recently reported on further murky donations to Weidel's constituency. The Bundestag administrative body told the party to provide information on a donation of €38,000 received by the AfD's Lake Constance branch.