Baradar will not be handed over to any second country and like other detainees, he has been released within Pakistan.
He will be provided with security and will be given the freedom to meet and communicate with anybody he wishes, media reports said.
The Pakistan Foreign Office had on Friday announced that he will be released today to "further facilitate the Afghan reconciliation process".
Baradar has been in the custody of Pakistani security agencies since his capture in Karachi in 2010.
He is the highest ranking Afghan Taliban prisoner freed so far.
Though Islamabad has freed 33 Afghan Taliban commanders since last year, Baradar's release was the most anticipated.
His release was personally sought by Karzai during his visit to Islamabad.
Analysts are skeptical whether Baradar will be able to influence the peace process, but the Afghanistan government thinks he could lead talks with the High Peace Council.
Kabul feels Baradar is a key figure in its efforts to kick-start the stalled peace process as most North Atlantic Treaty Orgnaistaion’s combat troops prepare to pull out of Afghanistan by the end of 2014.
Baradar was once considered the most influential Taliban leader after Mullah Muhammad Omar.
One of the four commanders who founded the Taliban movement, he was the leader responsible for the day-to-day campaign against United States and NATO troops until his capture by a joint team of Central Intelligence Agency and Pakistani intelligence operatives.
Afghan officials have said that at the time of his arrest, Baradar was holding talks with the Afghan government.
Pakistani intelligence was reportedly angered by his failure to inform them about these talks.
The US initially hailed his arrest as a blow to the Afghan insurgency but found out later that Pakistani agencies captured Baradar to scuttle the secret peace talks.
Born in the southern Afghan province of Uruzgan, Baradar fought in the war to expel Soviet troops from Afghanistan in the 1980s.
When the Taliban came to power in 1996, Baradar became deputy defence minister.
After the Taliban regime was toppled by US-led forces in 2001, he was among the hundreds of Taliban hardliners who fled over the border to Pakistan.
Image used for representational purpose only
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