Tds rate in case of transfer of fund from nro a/c to nre a/c

dear sir/madam,

kindly suggest me the amout of TDS to be deducted in cse of transfer of funds from NRO A/C to NRE A/C where the transferor is a NRI and citizen of U.K.  Assessee has made Fixed deposits in the NRO account in India and now he want to trasfer such funds to the NRE account opened in India itself. 

is TDS will be applicable to him and if yes, the rate of TDS. is there any tax releif to the assessee under DTAA between UK and INDIA. the assessee has also PAN issued in his name.

thanks in advance..