The changes are due to come into force from June 2020.
New electrical safety regulations raise the prospect of the highest risk rental properties not being covered by a legally binding electrical safety regime for a prolonged period of time, according to the Residential Landlords Association (RLA).
The changes, due to come into force from June this year, will remove the obligation for landlords to carry out electrical safety checks in Houses of Multiple Occupation (HMOs).
The obligation under the new rules will not apply until a tenancy is renewed or April 2021, whichever comes first.
This will leave some rental properties under no legally binding electrical safety regime for the interim period.
The new plans, which have been presented to Parliament for agreement, also contain weaker penalties for landlords failing to keep the properties they rent safe and reportedly complicate the process by which local authorities can issue penalties, making enforcement more difficult.
The RLA has written to the Ministry of Housing to express its concerns about the loophole being created for irresponsible landlords who otherwise would not carry out these checks.
It is calling on the government to delay the implementation of the new framework to provide time to address the problems being caused.
David Smith, policy director for the RLA, said: “Good landlords don’t need to be told to carry out safety checks but these changes to regulations leave tenants vulnerable to those landlords who are not so responsible.
"It is essential for the safety of tenants that the loophole being created is closed and we urge the government to delay implementation until that happens.”