Macquarie Group Ltd , Australia's top investment bank, agreed to buy U.S. asset manager Delaware Investments for $428 million in cash from Lincoln National Corp , continuing a trend of consolidation in the fund management business.

Macquarie, which has weathered the global financial crisis better than its global peers, has been on the lookout for acquisitions, taking advantage of falling asset prices.

The deal would boost Macquarie's total assets under management to over $300 billion, the bank said in a statement on Wednesday.

The acquisition of Delaware is a demonstration to our clients of the ongoing commitment we have to developing a global asset management capability with significant scale, product depth, research and investment capacity, Shemara Wikramanayake, global head of Macquarie Funds Group, said in a statement.

Delaware manages about $125 billion in assets and the deal was subject to regulatory approvals, Macquarie said.

Macquarie has still got a lot of surplus capital sitting there and they have a got a lot of powder. This is certainly a step in the right direction, CLSA analyst Brian Johnson said.

Lincoln, one of the largest U.S. life insurers, said the sale will help it focus both management and capital resources on its core businesses, insurance and retirement .

Goldman, Sachs & Co was Lincoln's financial advisor.

In June, Canadian insurer Sun Life Financial Inc bought the UK operations of Lincoln for about C$359 million ($326.1 million).

Industry experts expect a wave of consolidation in the fund management industry following BlackRock's $13.5 billion deal to buy an asset management unit of Barclays .

Bank of America has been trying to sell its Columbia Management unit, for instance.

Macquarie has used the previous market declines to buy up distressed assets. It bought BT's Australian operations in 1999 and ING Group's Asian equities business in 2004.

(Reporting by Denny Thomas in Sydney and S. John Tilak in Bangalore; Additional reporting by Saeed Azhar; Editing by Jonathan Standing and Rupert Winchester)

($1=A$1.20)

($1=1.101 Canadian Dollar)