London-based life insurance firm Rothesay Life, a subsidiary of Rothesay Holdco UK Limited, is preparing a 3.5 billion pounds ($4.4 billion) bid for reinsurance company Swiss Re’s unit in the UK, ReAssure.

The move comes after Swiss Re was planning an initial public offering (IPO) for its British unit.

In August 2018, Swiss Re revealed the IPO plans noting that it was important for ReAssure to have access to new capital to acquire more closed books.

Last year, Rothesay acquired a $15.20 billion UK annuities book from U.S. insurer Prudential Financial and a $1 billion portfolio of equity release loans from financial service company UK Asset Resolution.