Construction companies that want to work for the Illinois government would have to promise not to move out of state under a proposal moving through the Legislature.

Bidders on state construction contracts would have to sign affidavits affirming that the company will keep its primary employment base in Illinois.

The bill passed without opposition Tuesday in the House. It goes to the Senate.

The legislation comes as other states try to lure away Illinois companies in the wake of the state income tax increase.

Caterpillar Inc. recently told the governor that several other states are trying to persuade the company to leave its Peoria headquarters.