Europe is on the brink of a landmark ban on the world’s most widely used insecticides, which have increasingly been linked to serious declines in bee numbers. Despite intense secret lobbying by British ministers and chemical companies against the ban, revealed in documents obtained by the Observer, a vote in Brussels on Monday is expected to lead to the suspension of the nerve agents.

Bees and other insects are vital for global food production as they pollinate three-quarters of all crops. The plummeting numbers of pollinators in recent years has been blamed on disease, loss of habitat and, increasingly, the near ubiquitous use of neonicotinoid pesticides.

The prospect of a ban has prompted a fierce behind-the-scenes campaign. In a letter released to the Observer under freedom of information rules, the environment secretary, Owen Paterson, told the chemicals company Syngenta last week that he was ‘extremely disappointed’ by the European commission’s proposed ban. He said that ‘the UK has been very active’ in opposing it and ‘our efforts will continue and intensify in the coming days’.

Publicly, ministers have expressed concern for bees, with David Cameron saying: ‘If we do not look after our bee populations, very serious consequences will follow.’

The chemical companies, which […]