Growth in global agricultural production is expected to slow in the coming decade, the UN food agency and the OECD said in a joint report Thursday, warning threats to food security remain. The world's agricultural output is projected to grow at an average 1.5 percent annually from 2013 to 2022, the UN's Food and Agriculture Organization (FAO) and the Organisation for Economic Co-operation and Development (OECD) said in the report. That compared to an average increase of 2.1 percent a year in the last decade, said the OECD-FAO Agricultural Outlook 2013. "Production shortfalls, price volatility and trade interruptions remain a threat to global food security," it said. The report blamed the output slowdown on "rising costs, growing resource constraints, and increasing environmental pressures, which are anticipated to inhibit supply response in virtually all regions". The world's population is expected only to grow by one percent a year over the period, but price rises will be fuelled by stronger demand with consumption increasing in developing countries, it said. Growing populations, higher incomes, urbanisation and changing diets were all factors, it added. The document, which was released in Beijing, said that China was also expected to see slower output growth in the next decade with increasing resource and rural labour constraints. The number of undernourished people in China has fallen by almost 100 million since 1990, it said, even as the population has increased by 200 million. But the world's second-largest economy imported 12.9 percent of its food and agricultural products last year, up from 6.2 percent in 2001, and the rate could rise further, the report said. "With increasing production constraints and strong demand growth, additional agricultural imports may be anticipated," it said. It warned that increasing constraints on resources and more frequent and severe weather events due to climate change were key uncertainties in the country's agricultural outlook, along with whether high levels of economic growth would be maintained.