Azerbaijan’s President Ilham Aliyev has appointed his wife, Mehriban Aliyeva, as first vice president of Azerbaijan.

Aliyev's decree on the appointment was posted on the presidential website on February 21.

The decree did not specify what duties 52-year-old Mehriban Aliyeva would have in her new post although the constitution states that the first vice-president will deputize for the president while he is out of the country.

The posts of vice president and first vice president - a more senior position - were introduced last year after a constitutional referendum cleared the way for the president's powers to be devolved if he becomes incapacitated.

The referendum also extended the presidential term from five to seven years.  An earlier vote had scrapped term limits for the presidency.

The other vice-presidential post remains vacant.

Ilham Aliyev came to power in 2003, replacing his father Heydar Aliyev, who had ruled the oil-rich country since 1993.