A spokesman for Taoiseach Enda Kenny has said that the decision to send LE Eithne to aid in the rescue of migrants in the Mediterranean has still to be formally approved by the Cabinet.
Ireland may send the navy vessel to help with the migrant crisis in the Mediterranean.
The LE Eithne is expected to take part in a mission to prevent further migrant ship tragedies.
Thousands were rescued and 10 bodies recovered off the Libyan coast last weekend.
At least 1,750 people have died this year trying to cross the sea separating Europe from North Africa.
The Minister for Defence Simon Coveney has said it would be ready by Friday."
The EU had been accused of being too slow to react to the growing humanitarian crisis in the Mediterranean.
Recently a fishing boat carrying people from Libya sank killing up to 800, in what the UN has called the deadliest incident in the Mediterranean ever recorded.