Port delays have been a typical issuein Egypt which supplies about 10pc of the world's urea, according to Rabobank.

Meanwhile, natural gas shortages in key nitrogen production countries such as China, Iran, Pakistan, Venezuela and Trinidad and new 110pc taxes on all Chinese fertiliser exports have also restricted fertiliser exports according to International Fertiliser Industry Association (IFA).

The peak international trade body said while new fertiliser plants were meeting demand with more efficient production from the Middle East and North Africa, delays in some projects elsewhere had left supply lines vulnerable to demand surges, while increasingly stringent environmental laws were restricting fertiliser production investment.

IFA agriculture service director, Patrick Heffer believed global trade prospects were positive for virtually all fertiliser products.

A record 178 million tonnes of demand was anticipated in 2011-12 -up three per cent, with a further 2.3pc tentatively tipped for 2012-13.

But despite "massive investments in new capacity projects since 2009" adding significant new supplies of urea, DAP and potash, the supply landscape and investment in the near term was still difficult.

Last year IFA forecast that crop nutrition producers were looking to lift production by as much as 30pc by 2014-15 as they rushed to cater for food security demands.

Long-term investments in new production meant almost 250 capacity-related projects were planned by 2015 and a large number of expansions were scheduled at existing sites but IFA production and trade service director, Michel Prud'homme said domestic consumption was so far absorbing most of the increased sales from these plants.