The US federal government has released on the 14th of December 2023 a new set of requirements to reduce the climate footprint of the travels realised by its federal employees. The requirements include shifting to rail travels. It has fixed the following rule: federal employees will use rail for trips less than 250 miles (around 400km) when cost-effective and available, instead of taking an airplane or vehicle. For example it includes the journey between Washington and New York where traveling by train emits 92% less CO2eq emissions than flying.
The US is joining a team of progressive countries (Switzerland, France, the Netherlands) also incentivising rail travel for their civil servants.
The US government is also requiring the federal employees to use more electric cars and public transport when traveling locally.
More details here