The group is currently embroiled in a high-profile battle to ensure Eurostar keeps running its trains through the Channel Tunnel.
Alstom turned to BPPA in April 2009, handing out its first major UK public affairs retainer in recent years. The review is thought to be in its early stages, but several agencies have already held preliminary talks with Alstom.
The firm's UK comms director, Deborah Risby, confirmed that its UK public affairs could be overhauled as 'part of a country-wide review'. But she added: 'We are not in a position to confirm any next steps at the moment as this is still all under review.'
BPPA chairman Peter Bingle declined to say whether the agency would repitch for the work.
The review follows Alstom's failed attempt to stop Eurostar running German trains through the Channel Tunnel. Eurostar, the sole operator of passenger trains through the tunnel, has been using Alstom rolling stock. In October 2010, a UK court rejected Alstom's bid to stop Eurostar's EUR600m (£521m) order for trains made by Siemens.
Earlier this year, three Alstom directors were arrested in a UK corruption probe. The Serious Fraud Office said it believed bribes had been paid in the 1990s to win foreign contracts. The three men were later released without charge.