Deutsche Bank’s chief executive Christian Sewing has dropped his opposition to exploring a multibillion euro merger with German rival Commerzbank after persistently low interest rates and investor pressure over its grim performance forced him to consider other options.

“We still prefer our plan A and would love to do our own homework, and look at our strategic options later,” said a person familiar with the bank’s internal discussions, adding that executives were concerned that “some interested parties” were deliberately building up pressure to arm-twist management into acting now.

Cerberus, the US private equity group that is one of the biggest investors in both Deutsche Bank and Commerzbank, is actively pushing for a tie-up which the German finance ministry would welcome as a way to create a national champion in banking.