Bangladesh has joined China and South Korea by approving a currency swap to bail out Sri Lanka, which is facing its worst foreign exchange crisis, officials said Wednesday.

The central bank of Bangladesh on Tuesday approved a $250 million deal -- its first currency swap -- after Sri Lanka appealed for help to shore up its foreign reserves and ease pressure on the exchange rate.

"The board of the Bangladesh Bank has decided in principle to lend $200-250 million from Bangladesh's reserves to Sri Lanka for three months," Mohammad Sirajul Islam, a spokesman for the country's central bank, told AFP.

Bangladesh has built up $45 billion in reserves in recent years on the back of impressive garment exports and record remittances by its 10 million overseas workers.

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