A Crown Prosecution Service spokeswoman said that it would look into the case as soon as appeal papers are lodged:
Just a fortnight after 52 commuters died in the 7/7 bombings on the London transport system, three men walked onto the Underground and a bus carrying rucksacks packed with explosives.
The bombs never detonated, but all three were convicted of terrorism offences and sentenced to life in prison.
A fourth man backed out at the last minute and removed the battery from his bomb before ditching it in a bin in a West London park. He was jailed for 33 years.
A former government scientist has called into question the work of the prosecution's key expert witness in the case of the 21/7 bombers.
Sean Doyle, used to be the principal scientist at the government's Forensic Explosives Laboratory (FEL).
In a witness statement, Mr Doyle said a number of FEL scientists "openly expressed concerns" relating to the work of Dr Black.
The planned appeal by the four men convicted of a failed bomb plot hinges on whether the home-made explosives they were carrying were viable.
All four men claim that the plot was an elaborate hoax and that they never intended carry out a bombing.
However, the Forensic Explosives Laboratory (FEL), a top security government facility which tested the devices, concluded that they would have worked had the chemical recipe been correct.
It is this conclusion that will be called into question if the men file appeal papers.
A spokesman for the Criminal Cases Review Commission (CCRC) has said: "We are told by lawyers representing [the men] that an application is imminent."
Sean Doyle, the former principal scientist at the Government's Forensic Explosives Laboratory, has come forward to claim flaws in the evidence used to convict the failed 21/7 bombers.
He also cast doubt over the work of the prosecution's expert witness, Dr Stuart Black, at the 2007 trial.
In his witness statement, which forms a key part of their appeal, Mr Doyle sets out his "concerns regarding some of the scientific evidence presented by the prosecution".
Tests shown at the trial led to the conclusion that the four men's homemade devices were "potentially viable," despite failing to explode on the day.
The men claimed their targeted attacks on three tube trains and a bus were a hoax.
Four men jailed over a failed plot to bomb London in 2005 are launching a legal bid to overturn their convictions after a top government forensic scientist cast serious doubt about key evidence presented during their 2007 trial, Channel 4 News has reported.
Lawyers for Muktar Ibrahim, Yassin Omar and Ramzi Mohammed will lodge papers as early as tomorrow with the Criminal Cases Review Commission.
The fourth man convicted, Manfo Asiedu, will petition the Court of Appeal.