UPDATE 2-Motorola Solutions warns on quarterly revenue; shares fall

* 2nd-qtr rev $1.39 bln vs est $1.96 bln

* Adj earnings/shr $0.47 vs est $0.63

* Sees 3rd qtr earnings/share $0.35-$0.41

* Shares down as much as 6.4 pct premarket

(Adds CEO, CFO quotes; details; updates shares)

Aug 5 (Reuters) - Motorola Solutions Inc, a maker of walkie-talkies and radio systems, forecast a surprise drop in sales for the current quarter and reported lower-than-expected quarterly revenue and profit as sales declined in North America.

The company's shares fell as much as 4 percent to a three-month low in early trading.

Motorola Solutions will become more dependant on government spending after completing the sale of its enterprise business, which makes rugged mobile computers, tablets and barcode scanners, to Zebra Technologies Corp.

The remaining, government and public safety systems business, brought in two-thirds of Motorola Solutions' total revenue before the sale.

Spending by states and local governments has hardly picked up after a fiscal cliff scare led to budget cuts in the United States last year.

Motorola Solutions said it expects sales to drop 7-9 percent in the third quarter ending September, implying sales of about $1.94 billion at the midpoint of that range.

Analysts on average were expecting revenue to grow 0.3 percent to $2.12 billion, according to Thomson Reuters I/B/E/S.

Motorola Solutions said on Tuesday it expects to cut costs by about $300 million by the end of 2015 - more than its targeted $200 million.

The company, split from Motorola Inc in 2011, has cut costs and become leaner after being hurt by the government spending cuts as well as delayed orders from business customers.

Operating margins shrank to 9.9 percent in the second quarter ended June 28 from 13.6 percent a year earlier.

Total sales fell 7 percent to $1.39 billion, well below the average analyst estimate of $1.96 billion. Sales in North America dropped 14 percent to $841 million.

"Overall market demand in North America was down in the first half. But we do expect it to show improvement for the second half of the year," Chief Executive Greg Brown said on a call with analysts.

Net earnings attributable to Motorola Solutions increased to $824 million, or $3.22 per share, from $258 million, or 94 cents per share, a year earlier.

The income included a gain of $746 million from the enterprise business, which the company now counts among discontinued operations.

Excluding items, Motorola earned 47 cents per share, below the 63 cents analysts expected.

The company forecast earnings of 35-41 cents per share from continuing operations this quarter.

Chief Financial Officer Gino Bonanotte said the profit forecast was below second-quarter levels due to a higher tax rate.

Schaumburg, Illinois-based Motorola's shares were down 3.5 percent at $61.90 on the New York Stock Exchange Tuesday morning, after falling to $61.50.

They had gained about 14 percent in the year through Monday's close - almost in line with the S&P 500 index.

(Reporting by Sagarika Jaisinghani in Bangalore; Editing by Joyjeet Das)