ANKARA, May 22 (Reuters) - Turkey and Russia signed a memorandum on lifting trade restrictions against each other, Turkish presidential sources said on Monday, after Ankara and Moscow agreed at a meeting this month to settle trade disputes.

The memorandum was signed by Turkish Deputy Prime Minister Mehmet Simsek and his Russian counterpart Arkady Dvorkovich in Istanbul, the sources said.

The signing marked an important step in normalising and improving economic and trade relations between Turkey and Russia, they said.

A diplomatic crisis after Turkey shot down a Russian air force jet in 2015 near the Turkish-Syrian border prompted trade sanctions. Although relations have normalised since, some of the trade restrictions have remained in place.

The dispute brought Russia's grain supplies to Turkey to a virtual standstill.

Turkey is the largest Russian wheat importer after Egypt and Russian wheat is one of the most important sources of supply for Turkish flour millers.

(Reporting by Nevzat Devranoglu; Writing by Tuvan Gumrukcu; Editing by David Dolan) ((tuvan.gumrukcu@tr.com; +903122927021; Reuters Messaging: tuvan.gumrukcu.thomsonreuters.com@reuters.net))