Steam trains face being killed off by new environment laws, peers have warned.

Peers have asked for assurances that heritage steam enthusiasts will still be allowed to burn coal after new climate legislation comes in.

Peers pressed the Government to include an exemption in the Environmental Bill for steam railways, boats, vehicles and historic buildings.

There are plans to phase out coal-based power generation by October 2024, and restrictions on the domestic burning of coal have also been introduced. The Government has said heritage transport will still be allowed to use the fossil fuel, but peers have pressed it to enshrine that in law.

Speaking during the Bill’s committee stage, Baroness Neville-Rolfe, a Conservative peer and former minister, said she feared "an error could be made". She added: "It matters because this Bill could bring about the death of Thomas the Tank Engine and his nautical steamboat equivalent."

Lord Faulkner of Worcester, a Labour peer and the president of the Heritage Railway Association, said he wanted a ministerial assurance that the heritage steam sector "will be permitted to continue to burn coal".

"That guarantee should be placed in the Bill and enshrined in the Act when it finally passes," he added.

Lord Bradshaw, a Liberal Democrat peer and former railwayman, said: "Steam locomotives, in particular, and the associated steam engines employed elsewhere are generally now maintained to the highest standards by the most enthusiastic people and they bring lots of tourists into the most remote areas of the country."

The former Conservative cabinet minister Lord Forsyth of Drumlean, who is president of the Steam Boat Association of Great Britain and owns a steamboat, said: "Can the minister explain why she is not prepared to put in the Bill the exemption for historic vehicles of the kind to which she says the Government are committed?"

Responding, the Conservative frontbencher Baroness Bloomfield of Hinton Waldrist said: "I can confirm that heritage vehicles are not within the scope of the legislation, and that includes trains and boats."

Local authorities could also exempt historic houses in smoke control areas, she said, adding: "The Government are not doing anything that would impact on heritage vehicles, nor would they plan to do anything that would. An exemption is just not needed because these are not caught within the scope of the Bill."