ISTANBUL—Turkey’s lira slumped to yet another record low against the dollar on Wednesday, as political pressure on the central bank exacerbated a broader emerging market selloff amid concern that policy makers will prematurely cut interest rates.

The currency dropped for a sixth consecutive day, extending losses by as much as 1.3% to 2.5712 against the dollar as markets closed in Istanbul, breaching an all-time low of 2.5394 hit on Tuesday.

A steady drumbeat of political attacks on the central bank has distinguished the lira from other emerging-market currencies, which have weakened amid expectations that the U.S. Federal Reserve will start raising interest rates later this year, draining cash from developing economies. Yet as Turkey’s currency sank to fresh record lows, the government continued to demand lower interest rates to boost economic growth.

“Right now, Turkey definitely has no concerns about the exchange rate,” Economy Minister Nihat Zeybekci said Wednesday, adding that the government expects the central bank to keep cutting interest rates.

Coupled with a pickup in oil prices from six-year lows, the plummeting lira threatens to derail efforts to reduce inflation and could undermine economic growth as currency volatility ahead of June general elections deters investments.