Martin Marietta Materials posted a wider first quarter loss than Wall Street analysts expected Tuesday but the Raleigh company raised its guidance for the rest of the year after sales increased 21 percent.

Company officials also said they would proceed with plans to nominate four directors to rival Vulcan Materials Board of Directors on June 1. Martin Marietta said it spent $25.9 million in the quarter on its efforts to merge with Vulcan.

Martin Marietta initiated its $4.7 billion takeover of its larger rival in December, and the companies have been trading lawsuits and public barbs ever since.

Excluding business development expenses and acquisition expenses, Martin Marietta reported a loss of 30 cents per diluted share in the quarter, compared to a loss of 39 cents during the same period a year ago.

Net sales, however, increased 20.6 percent to $350.5 million and Martin Marietta shipped 9.6 percent more materials than it did during the first quarter of 2011.

The company, which provides the materials used to build roads, subdivisions and commercial buildings, is considered a bellwether for the construction industry.

Despite a slowdown in infrastructure spending and rising fuel costs, Martin Marietta Materials reported solid third-quarter earnings Tuesday.

The company, which produces rock, gravel and other materials used to build roads, subdivisions and commercial buildings, had sales of $464 million for the quarter that ended Sept. 30, up 4.6 percent from the same period in 2010.

Excluding one-time charges, the company reported earnings per share of $1.11. That was above the $1.09 a share that was the consensus among analysts who follow the company.

Martin Marietta now expects to ship anywhere from 2 to 4 percent fewer materials in 2011 than it did a year ago. The company’s fuel costs for the quarter rose 16 percent.

Raleigh-based Martin Marietta Materials has agreed to swap assets Lafarge North America.

The company announced Wednesday that it will receive Lafarge's quarry sites, concrete and asphalt plants and road paving business in Denver in exchange for cash and Martin Marietta's quarries and distribution yards along the Mississippi River.

The deal is expected to close within 60 days.

Martin Marietta produces rock, gravel and other materials used to build roads, subdivisions and commercial buildings.

Its business is closely tied to residential, commercial and government construction projects.

Martin Marietta's stock is has dropped about 20 percent over the past six months. The industry been hurt by uncertainty over future government spending levels and the prospects for approval of a long-term highway bill by Congress.

The state Department of Transportation is reporting the following road closures as of 10 a.m. Saturday:

Analysts with UBS Investment Research downgraded Martin Marietta Materials in a new report on fears that Republicans in Washington will scale back the nation's road building efforts as they seek to reduce spending.

UBS changed its rating from a buy to neutral on the Raleigh company, which produces rock, gravel and other materials used to build roads, subdivisions and commercial buildings.

"We see upside more limited as we think the expectation that 2011 begins a slow construction recovery is now generally priced in, and investors may not be prepared for continued political battles over road spending and other headwinds," the report states. "... we continue to like MLM shares for the longer term leverage to U.S. construction recovery."

The report cited House Republicans release of a draft of revisions to the House rules that would remove the requirement that highway trust fund dollars be used specifically for road building and maintenance.

Much of Martin Marietta's business is tied to residential, commercial and government construction projects, which makes it a barometer of the broader economy.