Australia finished two points ahead of India with 112 points in the final Test series before the April 1 cut-off date.
India leads T20I table, with South Africa in second place.
Australia regained the prestigious ICC Test mace and also won a cash award of $1million after beating New Zealand in the Christchurch Test by seven wickets and winning the series 2-0 on Wednesday.
- Smith leads Australia back to Test summit
Australia finished two points ahead of India with 112 points in the final series before the April 1 cut-off date.
Steve Smith will receive the mace and the cash award on behalf of his team in a ceremony to be held at a later date.
This is the eighth time Australia finished as the number one-ranked Test team at the annual cut-off date since the inception of the current rankings system in 2003.
It earlier topped the table each year from 2003 to 2009, before India claimed the number one spot in 2010 and 2011.
England ended as the number one-ranked side in 2012 before South Africa completed a hat-trick by retaining the top spot from 2013 to 2015.
India, by virtue of finishing second, will collect $500,000, while South Africa will pocket $200,000 and Pakistan $100,000 after claiming third and fourth positions respectively.
It was double delight for Smith’s men. They earlier topped the MRF Tyres ICC ODI Team rankings at the annual cut-off date, finishing comfortably ahead of second-placed New Zealand, followed by India, South Africa, Sri Lanka and England.
India leads the MRF Tyres ICC T20I Team rankings, with South Africa in second place following a 2-0 victory over England.
The two are followed by the West Indies, New Zealand, Sri Lanka, Pakistan, England and Australia.
A shuffling of the pack is on the cards as a lot of cricket in the shortest format of the game is still to be played before the April 1 cut-off date.
While the main round of the Asia Cup T20 will be played from February 24 to March 6 in Mirpur, the ICC World Twenty20 India 2016 will be staged from March 8 to April 3.
Test rankings (as of February 24, after the conclusion of the New Zealand-Australia series)
1. Australia 112 points
2. India 110
3. South Africa 109
4. Pakistan 106
5. England 102
6. New Zealand 96
7. Sri Lanka 89
8. West Indies 76
9. Bangladesh 47
10. Zimbabwe 05
ODI rankings (as of February 24)
1. Australia 126 points
2. New Zealand 114
3. India 113
4. South Africa 112
5. Sri Lanka 104
6. England 101
7. Bangladesh 97
8. Pakistan 87
9. West Indies 86
10. Afghanistan 47
11. Ireland 46
12. Zimbabwe 45
T20I Rankings (as of February 24, after the Asia Cup qualifying matches)
1. India 122 points
2. South Africa 119
3. West Indies 118
4. New Zealand 116
5. Sri Lanka 116
6. Pakistan 113
7. England 112
8. Australia 110
9. Afghanistan 77
10. Scotland 69
11. Bangladesh 64
12. Netherlands 59
13. Zimbabwe 54
14. Hong Kong 49
15. Ireland 48
16. UAE 42
17. Oman 32
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