By William James

LONDON (Reuters) - Britain on Thursday promised to free more sites for nuclear energy developments across England and Wales, seeking to attract private investment into Small Modular Reactors (SMRs) as part of its push to decarbonise the power network.

Prime Minister Keir Starmer's office announced plans to expand the list of possible sites for nuclear development and set out other reforms to streamline the planning process.

"This country hasn’t built a nuclear power station in decades. We’ve been let down, and left behind," he said in a statement.

Successive British governments have championed the benefits of SMRs - effectively small-scale nuclear plants - in search of a way to avoid the high upfront costs, planning delays and difficulty of securing investors associated with larger plants. But to date, no SMR projects have been built.

Attracting private capital is central to Starmer's overall plan for government following his election win in July, after he inherited a sluggish economy and then imposed rules on spending and borrowing to promote economic stability.

His bid to generate growth has already seen the announcement of planning broader reforms, particularly for large infrastructure projects.

There are currently eight sites approved for nuclear development. The new plan would encourage developers to put forward other possible sites and promises flexibility that could see SMRs located alongside power-hungry Artificial Intelligence data centres.

The new nuclear policy document builds on a consultation undertaken by the previous, Conservative government last year and will be subject to further consultation and parliamentary scrutiny before it is adopted.

A government competition to develop SMRs has been running since 2023, with four bidders still in the race for what could be multi-billion-pound technology development contracts. They are Rolls-Royce, Westinghouse, Holtec Britain and GE-Hitachi Nuclear Energy - an alliance between General Electric Co and Japan's Hitachi Ltd.

A previous SMR competition was launched in 2016 but did not proceed beyond the information-gathering stage and closed in 2017.

(Reporting by William James; additional reporting by Susanna Twidale; Editing by Kevin Liffey)