This work is concerned with the subject of language- identification (LID). Two central issues are addressed. The first is to analyse the trade-off between detailed acoustic modelling and robust estimation of acoustic and language models. The second to find the optimal combination of acoustic and language scores for language identification.. Experiments are carried out using the three languages American-English, German and Spanish from the OGI-TS . database. It is shown that on the average the acoustic modelling is able to recognise 46.3% of the phones correctly across the three languages. Insertion and deletion rate is 35.7% and 6.6%, respectively. Language-identification performance is 82.6% with the full set of acoustic models. The performance is increased to 83.7% after having . conducted 80 iterations of a hierarchical clustering in which phones are merged across the languages.