SINGAPORE, May 11 (Reuters) - Saudi Arabia, the world's top crude oil exporter, will supply full volumes of crude to at least four Asian refiners in June, five people with knowledge of the matter said on Tuesday.

The OPEC kingpin started easing supply cuts to buyers in May as OPEC, Russia and their allies, a group known as OPEC+, stuck to plans for a phased roll-back of oil production restrictions from May to July.

But state energy giant Saudi Aramco is also trimming supplies to a fifth Asia buyer in June within a permissible adjustment limit in the contract, they said.

Under the contracts, the seller or the buyer can adjust loading volumes, depending on demand and shipping logistics, using operational tolerance which ranges from plus to minus 10% of the contracted Saudi volume. (Reporting by Florence Tan; Editing by Muralikumar Anantharaman)