British Prime Minister Gordon Brown was setting out options for tougher anti-terrorism laws Wednesday, and was expected to propose granting police more time to hold suspected terrorists before they are charged with an offense. Brown was making a statement to lawmakers setting out a raft of suggested revised laws, likely to include a recommendation to allow the use of wiretaps in court cases, a practice currently banned in Britain. The proposed changes follow failed attacks last month, when a pair of luxury cars packed with gas cylinders and nails were found in central London and two men crashed a Jeep Cherokee loaded with fuel canisters and gasoline into security barriers at Glasgow airport's main terminal, setting it ablaze. Home Secretary Jacqui Smith said Tuesday she believed that there was now evidence that police needed to hold terrorism suspects for longer than the current limit of 28 days. In 2005, lawmakers rejected the government's bid to allow police to detain suspects without charge for 90 days, forcing it to accept the lower limit in Tony Blair's first parliamentary defeat. The main opposition Conservative Party said Wednesday it would oppose any attempt to raise the custody time limit. In an interview with Britain's The Sun tabloid, published Wednesday, Brown urged his opponents to "put party politics aside and look at the national interest. We are in a new world." "We are facing an al-Qaida who are trying to cause carnage," Brown said. "We have to show we are resolute and strong and steadfast in tackling what they are determined to do." Intelligence officers now believe there are around 2,000 suspected terrorists in Britain, Smith said, an increase from a figure of 1,600 given last year by departing MI5 domestic intelligence agency chief Eliza Manningham-Buller. "This all gives us a strong view that the time is right to reconsider whether we should allow longer than 28 days for pre-charge detention," Smith told Parliament's Home Affairs Select Committee. Six suspects have been questioned for 28 days since the 28-day rule was introduced last year - two of whom were charged in connected with an alleged plot to down US-bound airliners. A third man, Habib Ahmed, was charged by police in Manchester with keeping documents linked to terrorism and attending a terrorist training camp in Pakistan. The other three were released without charge, police said. Alan West, Britain's terrorism minister and former Navy chief, said police had been confronted with more sophisticated methods of terrorism, including encryption of computers and cell phones. He said that the international nature of many plots also posed problems. In a current case, 17 countries had been approached, he told the House of Lords on Tuesday. He didn't give details. Proposals to toughen anti-terrorism laws could set Brown on a collision course with civil liberties campaigners. Shami Chakrabarti, director of the human rights group Liberty, said extending the custody limit for terror suspects beyond 28 days would effectively create a new system of internment, "the most chilling and counterproductive tool in Britain's anti-terror history." Figures released last week showed that between September 2001 and March 2007, 1,165 people were arrested under terrorism laws, but only 241 were charged with terrorism offenses. Of those, 41 have been convicted in courts and 114 are awaiting trial, Home Office statistics showed. The Home Office said around 200 other offenders had been charged with criminal offenses not covered by anti-terrorism laws, including murder, firearms offenses and fraud.