The European Commission is set to delay the publication of proposals on sustainable farming and nature that were expected this week, with the impact of the war in Ukraine on food supply leading some countries to question the European Union's environmental push, reported Reuters.

The EU's "Green Deal" is overhauling all sectors, including agriculture, which produces roughly 10% of EU greenhouse gas emissions. Brussels has targets that include halving chemical pesticide use by 2030, and is drafting laws to make them a reality.

The European Commission (EC) was due to have made public on Wednesday two new proposals - binding targets to restore nature and a more sustainable pesticides law.

However, EU agriculture commissioner Janusz Wojciechowski on Monday said that the EU would not discuss pesticides at its meeting this week, meaning that the proposal's publication would be pushed back. He did not comment on the nature restoration plan.

Earlier, EU food safety commissioner Stella Kyriakides told national agriculture ministers in Brussels that the bloc had to shift to sustainable pesticide use but that the Ukraine crisis did not give the "political space" for a proper discussion now.

The EC will put forward measures to deal with the impact of Russia's invasion of Ukraine, which has driven up prices of wheat and barley, and raised fears of shortages.

Russia and Ukraine make up more than 30% of global trade in wheat and more than 50% for sunflower oils, seeds and meals.

One proposal will be to allow cultivation on land lying fallow, a practice that allows the environment to recover between farming cycles.

The measures are also set to include help for pig farmers, given pork exports to Ukraine are now cut off, and greater freedom to provide state aid.

A group of 400 scientists and food sector experts on Friday said abandoning sustainable farming practices would be counter-productive.

"These measures would not move us toward but further away from a reliable food system that is resilient to future shocks, and delivers healthy and sustainable diets," their statement said.

They called instead for a shift to crops less reliant on fertilisers produced using Russian gas, and more plant-based diets to cut the amount of grain needed for animal feed.