Somalia has pushed back a deadline to complete a parliamentary election from this Friday to March 15, a senior government official said, citing hurdles including insufficient funds and a row in one city over voting procedures.

Somalia, where no central government has held broad authority for 30 years, is in the midst of a protracted election process to choose a new leadership that has repeatedly been held up amid a power struggle between President Mohamed Abdullahi Mohamed and Prime Minister Mohammed Hussein Roble.

The parliamentary election started in November and had been due for completion on Friday. Under Somalia's indirect electoral process, it involves clan elders picking the 275 members of the lower house, who would then choose a new president at a date yet to be fixed.

"The lawmaker election which was supposed to be concluded on February 25 is postponed," Abdirahman Yusuf Omar, Assistant Information Minister, said in a statement late on Thursday.

"... This is due to challenges of severe drought... lack of election funds and insecurity."

Omar said a disagreement over how to conduct the vote in Garbaharey, the capital of the southern Gedo region, had also led to the extension.

He said so far the election of 175 lawmakers had been completed, and of 54 senators to parliament's upper house.

Data from the UN Office for the Coordination of Humanitarian Affairs shows 4.3-million people in Somalia are affected by drought, with 271 000 displaced as a result.

The al Qaeda-linked al Shabaab group, which frequently carries out gun and bomb attacks in Mogadishu and elsewhere in Somalia, has also been an impediment to the election.

In mid-February, a suicide bomber targeted a minibus full of election delegates, killing at least six people in Mogadishu. The delegates were unharmed.

Last week, International Monetary Fund's Somalia representative said a key IMF-supported programme funding military wages and other essential services could expire in May if there were any further delays to elections.