US President Joe Biden has pledged to build temporary silos to facilitate the export of grain out of war-torn Ukraine and address surging food prices amid Russia’s invasion.

“We're going to build temporary silos in the borders of Ukraine, including in Poland. So we can transfer [grain] from those cars into those silos into cars in Europe and get it out into the ocean, and get it out across the world. But it's taking time," President Biden said in a speech at the AFL-CIO convention in Philadelphia, where he discussed potential solutions to rising food prices across the country.

US and EU officials have been exploring efforts to build temporary silos in Ukraine and its neighbours to help get 20 million tons of grain onto the world food supply. In the next month, Ukrainian farmers will start the summer wheat harvest, but won’t have anywhere to store it, Ukrainian officials have warned.

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Pres. Biden said Tuesday that the grain couldn’t be shipped out through the Black Sea 'because it'll get blown out of the water' by Russia’s naval blockade. "I'm working closely with our European partners to get 20 million tons of grain locked in Ukraine out onto the market to help bring down food prices," he said.

Some 84 foreign ships are stuck in Ukrainian ports – many with grain cargoes onboard, and they fear they will be sunk by the Russian Black Sea Fleet should they try to export Ukraine's grain despite being from non-aggressor third countries. The US for now has ruled out sending military ships into the region, which would risk Russian retaliation.

The Americans have been working on a plan to export the grain through other countries by rail, but they acknowledged the overland routes are rife with logistical problems. Rail routes can only move a fraction of the grain that Ukraine normally exports from its Black Sea ports and Ukrainian trains operate on a wider rail gauge than that used by the rest of the tracks in Europe. Biden suggested that building silos was a better option for now and could help Ukraine buy some time.

Talks are ongoing between the United Nations and Russia, and separately with Turkey, that aim to broker a deal with Russia to allow Ukraine to restart grain exports via the Black Sea. But Biden administration officials and US lawmakers are sceptical of Russia’s efforts, since Moscow is demanding sanctions relief in return.