UK: The British government's terror law watchdog has urged police to use special stop-and-search powers sparingly, warning that overuse could damage community relations and lead to demands for their repeal.

In his annual review of the Terrorism Act 2000, Lord Carlile of Berriew QC repeated an earlier warning that companies renting executive jets should be subject to stricter regulation because of the risk of hijackings.

And he has told Home Secretary John Reid that customs officers are so "thinly spread" as to provide "no discouragement to terrorists" at British ports of entry.

Lord Carlile said the relationship between the police, customs and immigration officials was "excellent where the facilities and staff are adequate". But he added: "I remain of the view that customs officers in particular are thinly spread."

Recounting his own arrival at Heathrow airport from south Asia with gifts to declare, but finding no customs officers available and the telephone provided for the purpose inoperative, Lord Carlile said: "This kind of manpower weakness is no discouragement to terrorists. This is still a chorus complaint by Special Branch officers.

"The adequacy of staffing at HM Customs and Excise at and for ports of entry of all kinds is an important matter."

In response, Mr Reid said officers were deployed according to risk, with strike forces deployed to meet specific risks or where there were no permanent staff. "The time has long gone when small numbers of staff, carrying out the same and similar tasks each day in fixed locations, can provide the detection or the deterrent capability needed."

However, Lord Carlile later told the BBC's World at One programme he feared these strike forces were not sufficiently organised for their anti-terrorist role. "There's absolutely no doubt there remains a serious risk of terrorism, and that can arise at ports of entry."

On stop and search, Lord Carlile made clear there was a continuing need for Section 44 of the Terrorism Act, which enables police to declare a geographical area in which searches can be carried out without being founded on "reasonable suspicion". However, while these powers had "a greater utility" in the Greater London area, he said there was "little or no evidence" that Section 44 powers had greater potential to prevent an act of terrorism compared with normal police stop-and-search powers.

And he noted that no Scottish police force had used the powers, while he doubted whether Scotland was less at risk from terrorism than other parts of the country.