"Since the start of the year 1,200 immigrants have arrived by sea from Turkey. To control immigration the EU is giving six billion euros to Turkey. Something's not right, is someone not doing what they should be doing?" Salvini said as quoted by the Ansa news agency.
According to the deal, the sides agreed that Syrian refugees arriving in Greece would be returned to Turkey if their claim for asylum was rejected, while Syrian asylum seekers in Turkey would be resettled in Europe on a one-for-one basis.
Brussels, in turn, vowed to provide financial aid to the country to cover the costs of migrant reception, among other measures.
However, the Turkish authorities have repeatedly complained that the European Union has been failing to provide the promised funds and about the lagging speed of transfers.