Barzani has been president of KRG since 2005 and has continued to serve in the role despite his term expiring in 2013. He engineered several extensions through Parliament, roiling his opposition amid a security and financial crisis sparked by the rise of Isis in 2014 and the collapse of global oil prices.
Several of his Kurdish political opponents and Iraq's central Government accused Barzani of staging the referendum to shore up his shaky legal hold on the presidency.
His supporters, on the other hand, consider him the only credible candidate to lead the Kurds in a long-deferred quest for self-rule.
Mustafa Barzani, Masoud's father, led the peshmerga forces in multiple uprisings against Iraqi rule dating to the 1940s and held the largely ceremonial position of commander until his death in 1979.
Barzani and his powerful family had been the primary architects of a referendum held last month on independence from Iraq. His son is the head of the KRG security council, and his nephew is prime minister.
Voters overwhelmingly approved of the move, but Barzani has been repeatedly warned by Iraq's central Government, the United States and regional powers like Iran and Turkey that its results would not be recognised.
Barzani pressed on, even as Kurdish opposition groups expressed misgivings about the timing and scope of the vote.
Of particular concern was the provocative decision to hold the referendum in areas historically disputed between Baghdad and the Kurds, including Kirkuk - an oil-rich province that peshmerga seized during a chaotic withdrawal of Iraqi forces in the face of an Isis onslaught.
Immediately after the September 25 referendum, Iraqi Prime Minister Haider al-Abadi ordered that all border crossings, airports and oil facilities in the Kurdish region be turned over to federal control. Iran and Turkey threatened to close their borders with the Kurdish region.
Earlier this month, Abadi ordered Iraqi forces into Kirkuk and other disputed areas.
The show of force resulted in sporadic clashes that have since ceased as Iraqi and Kurdish commanders continued to negotiate over a settlement on who would control border crossings with Turkey and Syria in the northwest.
The United States did not initially oppose Abadi's military move, saying it supported Iraq's bid to impose federal control over disputed territory.
It has since urged Baghdad and Kurdish authorities to set aside hostilities and resume talks on revenue-sharing and borders.
