UPDATE: Gov. Jay Nixon said this afternoon that he'll call a special session to consider a major piece of economic development legislation unveiled by state lawmakers earlier today.

Shortly after a news conference announcing the tax credit package, a Nixon spokesman released this statement.

By working together in a bi-partisan way, we've taken another important step toward passing a major job-creation package in a fiscally responsible manner. 

"From day one, Gov. Nixon's priorities have been creating jobs and keeping our state's fiscal house in order. The Governor intends to call the General Assembly into special session to focus on passing a bi-partisan jobs package and moving our economy forward.

The Governor is due to give a "major" speech on economic development in Creve Coeur on Thursday. Legislative leaders said they plan to sit down with the Governor to discuss their plan early next week.

Also, more details of that plan became available at a news conference to discuss it Wednesday afternoon in St. Louis. Among other things, the package would:

• Cap historic tax credits at $80 million, with a separate $10 million cap for projects receiving less than $275,000 in credits. Currently, historic credits are capped at $140 million, with small projects exempt from the cap.
• Cap low-income housing tax credits at $110 million for a category of credits worth 9 percent of a project's value and $20 million for a category worth 4 percent. Currently the caps are $130 million and $60 million, respectively.
• It would end the 4 percent low-income housing tax credits after 2015, and require re-authorization of both the historic and 9 percent low income programs in 2018. It would also prohibit combing historic and 9 percent low-income credits on the same project.
• It would create the Aerotropolis Tax Credits, worth $360 million over 16 years, to reduce costs of flying goods abroad from Lambert, and subsidize the cost of building warehouses to house foreign trade.
• It would create the Missouri Science and Innovation Reinvestment Act, dedicating a stream of tax revenue from science and technology companies into a fund for startups.
• It would cut the annual cap on the Distressed Areas Land Assemblage Tax Credit to $15 million from $20 million
• It would make renters ineligible for the Senior Citizen Property Tax Credit.
• It would give sales tax exemptions to data centers to locate in Missouri.
• It creates Amateur Sports Event Attraction Tax Credits, capped at $3 million a year for six years.
• It would change the structure of the Missouri Housing Development Commission, replacing the current board of five statewide elected officials and four appointees of the Governor with a six-member panel. Two members would be appointed by the House Speaker, Senate President and Governor.

Many of the recommendations are similar to those made last year by the Governor's Tax Credit Review Commission.

Our earlier story is below:

State legislators have reached an agreement on a tax credit deal that would include subsidies for data centers, science startups and a Chinese cargo hub at Lambert-St. Louis International Airport.

The plan — hotly debated but not passed during spring's legislative session — will be unveiled later today by House Speaker Steve Tilley and Rob Mayer, president pro tem of the Senate.

The people familiar with the plan's details say it cuts state spending on tax credits — a key goal of Gov. Jay Nixon — while also creating new programs that have long been priorities of the St. Louis business community.

It would create the Missouri Science and Innovation Reinvestment Act, which would dedicate some tax revenue from science companies into a funding pool for startups. It would also create new tax credits for data centers. Most prized by St. Louis-area groups, though, it would set aside $360 million in tax credits for flights and buildings around a proposed international cargo hub at Lambert.

The plan achieves this by imposing new caps on historic and low-income housing tax credits, $90 million and $130 million respectively. Each program would have a seven-year sunset and there would be new restrictions on "stacking" the two programs. It also will — in the words of one lawmaker — "blow up" the Missouri Housing Development Corp., which awards the low-income credits, by replacing its current board with a six-member group, with two members apiece appointed by the Governor, House Speaker and Senate President.

To pass the legislation, lawmakers would likely have to go a special session, something Nixon said he would not do without broad agreement. Wednesday morning, the governor's office said it had not yet been briefed on the plan and had no comment. Nixon is due to give a major speech on economic development on Thursday in Creve Coeur.