Carwyn Jones is expected to focus on unity between Labour in Wales and at a UK level when he speaks to the party's conference in Brighton.
The First Minister and Welsh Labour leader is also expected to make a series of criticisms of the UK Government's Brexit approach, including the Prime Minister's Brexit speech in Florence, what he'll call 'the lost months of negotiation' and the effects of the Withdrawal Bill on devolution in Wales.
His hailing of Labour's party unity will be a direct response to accusations that during the election campaign Welsh Labour was attempting to distance itself from the UK party and its leader Jeremy Corbyn.
He's expected to say,
Labour has also frequently been criticised for sending mixed messages over Britain's future relationship with the European Union.
Senior figures within the party have sometimes seemed to be at odds with each other about what should happen after Brexit and that includes the two Labour leaders who've called for different levels of involvement with the single market.
But Carwyn Jones is expected to say any differences of emphasis shouldn't prevent the party uniting behind a common position.
Watch our Political Editor Adrian Master's report below: