Belarussian potash producer Belaruskali may export 18 percent less of the crop nutrient in 2016 unless the global economy improves and demand revives, the head of the state-owned company's trading division said on Wednesday.

Potash exports by Belaruskali, the second-biggest global producer, will range from 7.5 million to 9.3 million tonnes this year, compared with last year's 9.2 million, said Elena Kudryavets, director general of Belarusian Potash Company (BPC).

The estimates are "very conditional" on the economy, Chinese demand and crop weather, she added.

"We have a saying in Russian, 'you can plan, but God will decide,'" she said in a phone interview from Washington, where BPC and Belaruskali were meeting U.S. legislators. "The market is not easy."

In the first quarter, Belaruskali production fell 700,000 tonnes and exports dropped 500,000, about 30 percent, she said.

Potash prices have tumbled over the past year, under pressure from bloated capacity and weak currencies in major consumers such as India and Brazil.

Belaruskali produced 10.5 million tonnes last year, said the company's director general, Ivan Golovaty, who declined to estimate 2016 production. It is capable of producing 12.6 million tonnes, he said.

Major rivals Potash Corp of Saskatchewan and Mosaic Co have cut production in the past year to support falling prices.

Belaruskali resumed U.S. potash exports last year after a six-year break, following the 2013 breakup of its sales partnership with Russia's Uralkali. Some U.S. senators lobbied last year for sanctions against certain Belarussians to apply to Belaruskali, but Kudryavets said the miner has never faced sanctions.

BPC has started talks with Chinese buyers on a 2016 supply contract and an agreement in May is possible, Kudryavets said. She declined to comment on how far apart the sides are, with analysts expecting a sharp discount from last year's $315 per tonne.

"We are discussing the positions of each party and I hope as always that we will find a compromise," she said.

China supply contracts, which include buyer Sinofert Holdings Ltd, traditionally set a global price floor. Contracts with Indian buyers usually follow, but Kudryavets said it's possible those agreements will get done first this year.

Even as some analysts say there is too much capacity, Belaruskali is building new potash mines. The Garlyk mine in Turkmenistan is likely to start up in March 2017 and produce no more than 200,000 tonnes in its first year, Golovaty said.