Russia will begin delivering its advanced S-400 missile defence system to Turkey in 2019, the Interfax news agency cited Russia’s state arms exporter Rosoboronexport as saying on Tuesday, Reuters reported.

Rosoboronexport also said on August 21 that it would stop conducting its sales to foreign customers in U.S. dollars, allowing purchases in local currencies.

The announcement comes as Turkey faces a crisis over its weakening lira currency amid worsening relations with the United States.