(Reuters) -Australian money manager AMP posted higher half-year earnings, citing strong net cashflows in its wealth platform and margin improvement in its banking unit, but fell short of market expectations, which sent its shares lower.

The 176-year-old wealth management firm's stock fell as much as 4.2% to A$1.60, marking its biggest intraday decline in two weeks. It posted six-month underlying net profit of A$131 million ($85.19 million), below Visible Alpha consensus estimate of A$136.7 million.

CEO Alexis George said the result underscored "continued discipline and delivery of the strategy", citing improving flows in its wealth segment and cautious growth in banking.

The AMP Bank division posted a 2.9% rise in profit to A$36 million, with net interest margin (NIM) ticking up to 1.30% from 1.28% a year earlier, aided by fixed-rate loan rollovers and a growing investor segment.

For the full year, AMP expects the bank which has been struggling to maintain lending volume growth to maintain net interest margin at around 1.30%.

The group's new digital bank AMP Bank GO, launched in February, attracted about 7,500 customers and A$123 million in balances by June-end.

Group costs remained a focus, with controllable costs falling 4.4%, helping to offset inflationary pressures and lower investment income.

AMP's Platforms segment's profit rose 7.4% to A$58 million, supported by net cash inflows of A$2.3 billion, up nearly 99% year-on-year. New adviser sign-ups and rising demand for its Managed Portfolios helped lift assets-under-management to A$153.9 billion.

Analysts at Jefferies attributed the miss to lower underlying earnings from savings and investments and group's corporate division.

"Overall, we view this as a solid result and are not overly concerned by the miss versus consensus," added Jefferies.

AMP declared interim dividend of 2 Australian cents per share, in-line with last year's payout.

($1 = 1.5378 Australian dollars)