Despite being one of President Donald Trump’s biggest campaign promises, Republican sources have said the president might put off implementing his $1 trillion infrastructure plan until 2018.

Sources told Axios Trump is more likely to focus on immigration, healthcare and tax issues this year and put off infrastructure until next year. The development is discouraging for an industry that was excited with Trump’s win, largely thanks to his infrastructure promises, Construction Dive reports.

Construction stocks fell following the news last week. Among those that suffered, U.S. Steel dropped 7.85%, Martin Marietta lost 4.7% and Caterpillar dropped 2.7%.

On Monday, Trump told the industry not to worry, promising to spend "on infrastructure big" in remarks made just before his Tuesday address to Congress, Bloomberg reports. The news was met with a market surge. A Bespoke Investment Group basket of infrastructure stocks jumped over 3% Monday to become one of the day's strongest industries on the S&P 500.