London attack: Defiant MPs return to business
The police must "want for nothing" in resources to fight terrorism, a Welsh Tory MP who served in the Met has said.
Gower MP Byron Davies spoke in a Commons debate following the attack on Wednesday which left four people dead.
Plaid Cymru MP Liz Saville Roberts warned against reacting to "warped ideology" with "unworthy responses" that could promote extremism.
Prime Minister Theresa May said the Commons debate had shown "normality" and defiance of terrorism.
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Mr Davies, a member of the home affairs committee, spoke of his experience serving under counter-terrorist command in London during the 1980s, tackling Irish and Middle Eastern terrorism.
"I know only too well the challenge that's faced by police," he said, adding that he wanted to reinforce the message about resources, saying all police and security forces fighting terrorism should "want for nothing".
Ms Saville Roberts told MPs that their return to the Commons on Thursday was "not a show of defiance" but "a show of respect for the dead and the injured".
She asked Mrs May: "Do you agree with me that we must not react to such a warped ideology with unworthy responses?"
The prime minister said the response of MPs had been "absolutely appropriate".
"It has shown gratitude for the bravery of the police and our emergency services," Mrs May said.
"It has shown respect and concern for those who have been the victims of the terrible attacks that took place but also it has shown normality
"I think that is what is important as we defy the terrorists and as we work to defeat them."
Rhondda MP Chris Bryant called for a shield to be unveiled in the Commons in honour of PC Keith Palmer, who died after being stabbed by the suspected terrorist.
The Labour member said it reflected a custom by which murdered MPs such as Ian Gow and Airey Neave were honoured.
"He was our shield and defender yesterday," he said.
Earlier, Kim Howells, the former Pontypridd MP who served chairman of Parliament's security and intelligence committee, told BBC Wales it was very "difficult" to contain terrorist threats in a democracy.
"We don't live in a police state and as a consequence of course there's a very good chance that someone will always get through.
Lord Carlile, the UK government's former independent reviewer of terrorism legislation, said the security services had enough powers to deal with the threat from terrorism.
"It was definitely predictable that there would be a low-technology attack of this kind somewhere," the former Welsh Liberal Democrat leader told BBC Radio Wales.
"We may have to consider the question of whether all police should be armed around major public buildings and places of public resort but those are lessons learned matters."
Welsh Assembly committees met as scheduled on Thursday following the suspension of proceedings in the Senedd on Wednesday.
Committee chairmen paused proceedings at 0933 GMT to observe a minute's silence.