KIEV (REUTERS) - Delivery of US$2 billion (S$2.5 billion) credit to Ukraine from Russia, the second tranche of a promised US$15 billion aid package, has been delayed until Friday, a Ukrainian government source said on Wednesday.

A first tranche of US$3 billion, aimed at helping the ex-Soviet republic pay foreign debts this year and prop up its national currency amid widespread unrest, was disbursed at the end of December.

Ukraine's interim government had been hoping a second tranche of US$2 billion would be delivered soon by Russian purchase of Ukraine-issued eurobonds.

But a Ukrainian government source said: "The deal has been put off until Friday for technical reasons. We expect the money to come on Friday."