Lobbyists for Monsanto remain barred from the European parliament after the US agrochemical giant refused to attend a public hearing about allegations it unduly influenced research into the safety of glyphosate, used in its RoundUp weedkiller.

It was the first time new public scrutiny rules have been deployed to punish firms that ignore a parliamentary summons. Monsanto officials won’t be able to meet MEPs or access parliamentary meetings and resources when the decision is implemented.

The parliamentary meeting, on 11 October last year, was called over allegations that Monsanto influenced research into the safety of glyphosate, which is a key component of its €4.02bn a year RoundUp weedkiller brand. In July, California added glyphosate to its list of carcinogens.

Philippe Lamberts, president of the Greens/EFA group in parliament, then said US companies must “accept the democratic control function of the parliament. Monsanto cannot escape this. Monsanto has to face the questions of parliamentarians and should not hinder the clarification process.”

Monsanto said in a letter that the meeting wasn’t the right forum to question the credibility of the scientific output of either the independent EU agencies or those in third countries, according to a tweet from Emmanuel Foulon, a press officer at the European parliament.

MEPs called for the hearing after leaked court documents raised concerns about the company’™s influence on RoundUp research and revealed internal debate about the product i™s safety, the Financial Times reports.

Monsanto said the documents were taken out of context.

The next step was for the president of the European parliament to send the decision to the five MEPs dealing with administrative matters, for approval. The secretary-general of the parliament has implemented the ban.

The ban was a serious setback for Monsanto, which spent between €300,000 to €400,000 on lobbying in Brussels in 2015 to 2016, according to the Corporate Europe Observatory guide to EU lobbying.