New rules on car booster seats for children have been delayed.

Backless booster seats for smaller children were expected to be outlawed in December, but it has been delayed.

Currently all children travelling in a car must use a car seat until aged 12 or 135cm tall, whichever comes first.

It means children weighing 15kg, which could be as young as three, can travel in backless booster seats, which concerns safety experts.

Under the proposed changes backless booster seats will only be approved for use for children taller than 125cm and weighing over 22kg.

Legislation on who is required to use a child car seat is set by the government, but the technical specifications for child car seats are set internationally by the United Nations.

The UN process is ongoing, then the European Union needs to adopt it for it to pass as law in the UK. The Department for Transport say it’s likely not to be brought into force until March 2017.

The new rules are being introduced because safety experts think backless booster seats do not offer protection for a child if a car is involved in a side-impact crash.

Once the changes go ahead, they will only apply to newly sold booster cushions. Parents who use old booster cushions that comply with the existing regulations will not be breaking the law.