Defence spending should increase following the Salisbury nerve agent attack, the Tory chairman of the Commons Defence Committee has warned.
Dr Julian Lewis told MPs the time had come to recognise that 2% of GDP was "not enough" to spend on defence "when we are reverting to the sort of adversarial relationship when we used to spend a much higher proportion of GDP in ensuring that this country was well defended".
His comments came as Prime Minister Theresa May gave a statement in the Commons updating MPs on the incident in Salisbury.
Mrs May responded: "Of course as we have been looking through our national security capability review and our modernising defence programme review, what we are doing is ensuring that for the variety and diversity of threats that this country faces, we have the resources and the capabilities available to deal with those threats, but of course as those threats diversify, not all of them will be responded to by what is conventionally normally considered to be defence."
Asking a question after Mrs May's statement, Dr Lewis (New Forest East) said: "No reasonable person can possibly doubt that the Russian Government has behaved with arrogance, with inhumanity and with contempt, not least in failing to respond to the Prime Minister's deadline which it surely would have done if it had known it was innocent of this charge.
"In welcoming the Prime Minister's expulsion of 23 diplomats who are really intelligence (agents), I ask her to make it clear that any retaliation in kind by the Russian Government will be met by further expulsions, possibly including even the ambassador, who spends so much time coming to talk to us in this place bemoaning the poor state of Anglo-Russian relations.
"And will she accept that Russia traditionally respects strength and despises weakness, and that the time has come to recognise that 2% of GDP is not enough to spend on defence when we are reverting to the sort of adversarial relationship when we used to spend a much higher proportion of GDP in ensuring that this country was well defended?"
Mrs May responded: "There are other measures we stand ready to deploy at any time should we face further Russian provocation."