Rising investment costs and falling profitability at the British carmaker, whose profits have propped up its weaker parent for the past year and half, combined with a drop into the red for the Indian company's domestic business.
JLR said operating margin was 14 percent in the December quarter, down from 17 percent a year ago, also due in part to a shift towards less profitable models.
JLR expects operating margin to remain stable in the coming quarters, Chief Finance Officer Ken Gregor told reporters, describing earlier margins as "extraordinary".
"The challenge for us as a business is to sustain at roughly the levels that they are at right now," he said.
Increasing reliance on lower-margin models like the Land Rover Evoque and Freelander and adverse currency movements saw JLR's profit margin fall, and free cash flow turned negative just months after it paid its weaker parent a maiden dividend.
JLR's cheaper, lower-margin Evoque and Freelander compact SUVs accounted for 52.5 percent of all Land Rover retail sales in the quarter, up from 43.7 percent a year earlier.
Currency fluctuations shaved off 50 basis points from JLR margins in the December quarter, the company said. The pound rose 0.7 percent against the dollar during the quarter, denting profits earned in the United States.
Tata's net profit for the third quarter of the financial year ending March 31 came in far below market estimates at 16.28 billion rupees ($303 million), down 52 percent on the year and the first fall since the three months to September 2011.
Analysts had expected average profit of 28.9 billion rupees, according to Thomson Reuters Starmine.
"Over the next couple of years, they are unlikely to generate much cash. That's a worry," said Joseph George, analyst at IIFL Institutional Equities in Mumbai.
JLR had net cash of 437 million pounds ($684 million) at end-September, but as it ploughs money into a new engine plant in Britain and a factory in China, it will no longer drive cash generation at its owner, Asia's seventh-biggest carmaker by market value.
Shares in Tata Motors, which is also listed in New York , fell 2.5 percent in Mumbai on Thursday before the results. The broader market ended down 0.6 percent.
JLR's cash was the primary reason behind an improvement in Tata Motors' consolidated net adjusted debt to operating EBITDA ratio to 0.98 in the year to last March from 1.21 in the previous year, ratings agency Fitch said in a recent note.
The maker of sleek Jaguar saloons and rugged Land Rover sport utility vehicles (SUV), raised $500 million in fresh debt last month and said it would raise funds from capital markets and banks to fuel its capital expenditure as required.
In China, the world's biggest auto market, JLR sales jumped 71 percent in 2012, making it the marque's No.2 market after Europe. JLR is investing $1.7 billion with local partner Chery Automotive to build a factory in China.
JLR contributed around 90 percent of Tata Motors' net profit in the last financial year, so its margins are scrutinised more by investors than those of Tata's domestic business.
The Indian automaker's core domestic business making trucks, buses and cars lost 4.58 billion rupees ($85 million) in the quarter, against profit of 1.74 billion a year earlier, as revenue fell 20 percent.
Operating margin for the India business fell to 2.2 percent from 6.7 percent a year earlier. The Indian parent's chief financial officer said the margin was one of its lowest ever.
The external environment and overall economic activity in India remained challenging, C. Ramakrishnan said, adding: "demand continues to remain under pressure for our products."
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Tata Motors profit falls
(PTI) Hit by a demand slump, homegrown auto major Tata Motors today reported 52.2 per cent decline in consolidated net profit for the third quarter ended December, 2012, at Rs 1,636.01 crore as Jaguar Land Rover margins get hit.
The company had posted a net profit of Rs 3,422.7 crore in the same period last fiscal, Tata Motors said in a filing to the BSE.
Consolidated total income from operations stood at Rs 46,089.5 crore during the third quarter as against Rs 45,260.25 crore in the same period last fiscal. The company said the growth in revenue was on the back of strong demand, growth in volumes and favourable market mix at Jaguar Land Rover (JLR).
On a standalone basis, the company had a net loss of Rs 458.49 crore in the third quarter ended December 31, 2012 as against a standalone net profit of Rs 173.67 crore in the same period last fiscal.
Standalone total income from operations during the period under review stood at Rs 10,630.09 crore as against Rs 13,337.9 crore in the year-ago period.
During the third quarter, Tata Motors sold a total of 2,05,291 vehicles as against 2,31,328 units in the same period last fiscal.
JLR wholesales for the quarter ended December 31, 2012, grew 9.9 per cent over corresponding period last year to 94,828 units, Tata Motors said.
While Jaguar volumes for the period stood at 15,043 units, Land Rover volumes were at 79,785 units. Growth in volumes is driven by continued strong demand from China and sales of Range Rover Evoque and Freelander.
JLR revenues for the quarter were at GBP 3,804 million, up 1.5 per cent from GBP 3,749 million during the corresponding quarter last year. Profit after tax for the
quarter was at GBP 296 million as against GBP 393 million in the corresponding quarter last year, it added.
In the domestic market, commercial vehicles sales for the quarter ended December 31, 2012, stood at 1,38,963 units, driven by the LCV segment and passenger vehicles sales stood at 54,675 units, it said.
Shares of Tata Motors ended the day at Rs 296.70 per scrip on the BSE, down 2.59 from the previous close.