Jakarta, June 4 -- Bank Indonesia (BI) has ramped up its market interventions to defend the rupiah after the currency breached a historic critical threshold, tumbling to around Rp18,000 per US dollar as of Thursday.

The aggressive move comes as the Indonesian currency is challenged by escalating Middle East tensions, high global energy prices and seasonal surge in domestic corporate demand for foreign currency, according to BI Senior Deputy Governor Destry Damayanti.

"Bank Indonesia continues to be present in the market and is increasing the intensity of its interventions to ensure that market mechanisms operate smoothly and the stability of the rupiah exchange rate is maintained," Damayanti said in her statement on Thursday.

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