On 31 August the yuan hit its lowest point since devaluation on 11 August.
Special drawing rights account for less than 3% of central bank reserve assets, economists say.
Tenge is trading down 21.57% at 252.60 per US dollar as at 10.20am GMT, after Kazakhstan freed currency.
Move comes as IMF awaits further reforms to China's currency policies.
State Bank of Vietnam has raised its reference rate by 1% to 21,890 dong per US dollar.
IMF praises China's recent steps allowing market forces to have greater role in determining exchange rate.
People's Bank of China's fresh devaluation by 1.1% raises fears of global currency war.
USD/CAD has broken through the 2009 high to its highest since 2004 on 24 July.
The central bank has dropped the phrase that the currency is 'overvalued' in its latest statement.
The National Bank of Hungary slashed the main rate by 15 basis points to 1.35%.
The currency has triggered a major bearish signal by breaking a channel support.
Declining global oil and dairy prices expected to weigh on Kiwi dollar.
Meanwhile, the rand is hovering near a 12-year low vs dollar.
British banks RBS, Barclays, Standard Chartered and HSBC have been named in investigation.
Morgan analysts, led by Serena Tang, opined that in the most optimistic scenario, the gush could exceed $1.2tn.