Lord West, Gordon Brown's Security Minister, was drawn into more controversy by the Conservatives last night after they accused him of producing an "inconsistent" assessment of Britain's security.

Lord West, Gordon Brown's Security Minister, was drawn into more controversy by the Conservatives last night after they accused him of producing an "inconsistent" assessment of Britain's security.

The Tories criticised the former head of the Royal Navy after he claimed the UK was better prepared to thwart terrorists than any other country and insisted there had been a "dramatic improvement" in the security since the Prime Minister took over in June.

David Davis, the Shadow Home Secretary, quickly pointed out how earlier this month Jonathan Evans, head of MI5, said the security services were now aware of 2000 people in Britain involved in terrorism plots and that the true figure could be double that given threats of which they were unaware. Moreover, Mr Evans pointed out this threat level had increased by 25% on the previous MI5 assessment of 1600 known terrorist suspects briefed in 2006.

Mr Davis said: "On November 5, the head of MI5 publicly set out the growth' in the domestic security threat, saying: I don't think this problem has yet reached its peak,' explaining we will not be able to cover every potential threat.' "Today, Lord West says we face a steadily declining threat,' claiming our counter-terrorism defences are ahead of all countries in the world on the protection front.' It is not likely to enhance public confidence when the head of the Security Service and the Security Minister give such inconsistent assessments," he added.

Nick Clegg, for the Liberal Democrats, was also not impressed with the Security Minister, noting: "First Lord West flip-flops over 28 days, then he brags about Britain's preparedness. This is not the way to improve public confidence in national security."

The ex-First Sea Lord, who in the summer became a member of Mr Brown's "government of all the talents", dubbed a Goat, hit the headlines last week after openly admitting he was not personally convinced of the case for extending the 28 day pre-trial detention period for terror suspects - even though this is government policy. Within an hour, however, and after a visit to No 10, the peer emerged to insist he was fully convinced of the need to extend the 28-day detention period.

He denied being "hauled in" to see the PM after his initial comments and pleaded he was a "simple sailor" who had failed to make himself properly understood the first time.

Elsewhere, Ruth Kelly, Westminster's Transport Secretary, yesterday made clear on the back of last week's security statement by Mr Brown that airport-style security scanners would not be automatically installed at all main train stations. She stressed such matters would be looked at in a "proportionate way" and operational matters were up to the police.

She highlighted the issue of design, pointing to the measures at Glasgow Airport and the terror incident over the summer when those in the vehicle which crashed into the terminal had to take "a rather convoluted route" and were unable to pick up speed.