* Competition, currency, unrest take toll
* Group total users up 4 pct to 147.3 mln
* ARPU continues to decline in key markets
* Shares down 2.0 pct (Adds MTN, analyst comments, background)
By Gugulakhe Lourie
JOHANNESBURG, May 6 Customers of MTN (MTNJ.J) spent less on calls in the first quarter, the company said, prompting a 2-percent fall in the shares of Africa's largest mobile phone operator.
Average revenue per user (ARPU), a key industry measure, was hit by intense competition and currency swings, falling 10 percent in South Africa and 6 percent in its key Nigeria market.
ARPU in Syria, which has been battered by political unrest, slid 12 percent and fell 5 percent in Ghana.
"Increasing competition might be a concern and (there is) declining ARPU in some markets," said a telecoms analyst who asked not to be identified.
The stronger rand will also mean less of a benefit from overseas revenues, he said.
MTN said it added more than 5.7 million users in the first quarter, bringing the group total to 147.3 million, and raised its 2011 subscriber growth target by 9 percent to 18.4 million.
Shares in MTN were down 2.0 percent at 130.64 rand by 1321 GMT, underperforming Johannesburg's Top-40 index .JTOPI which edged up 0.6 percent.
The Africa and Middle East-focused operator, which faces competition in Nigeria from rivals Bharti Airtel (BRTI.BO) and Etisalat ETEL.AD, operates in several tough markets.
Guinea's government has seized assets belonging to MTN and is taking over the running of the company in a row over payment of a 15 million euro ($21.80 million) fee. MTN said on Thursday it was negotiating with that government. [ID:nLDE7441MF]
The South African unit, which competes with its larger rival Vodacom (VODJ.J) and other two smaller operators, recorded a 1.9 percent rise in users to 19.2 million.
(Reporting by Gugulakhe Lourie; editing by David Cowell)