LONDON (Reuters) - Prime Minister Theresa May, answering questions about Britain’s response to Russia’s suspected involvement in a poisoning in England, said her government was conducting a review of visas issued to wealthy foreign investors.

May told members of parliament on Tuesday that Britain’s home secretary was reviewing investor visas, although the checks on possible loopholes were not specifically focussed on Russia.

“I think it is right that we look generally to see whether this is a part of our visa regime which is being used properly,” she said.

Britain has ordered the expulsion of 23 Russian diplomats and has said it will consider other measures following the March 4 poisoning of former Russian spy Sergei Skripal and his daughter with what London says was a Soviet-era nerve agent.

May said 25 countries have now moved to expel Russian diplomats and she also noted NATO’s decision to expel seven diplomats from Russia’s mission to the alliance.

“I welcome the international support that we have garnered,” she said. “This isn’t just a matter of the UK position and working with the UK. I think it is the national security interests of the countries concerned.”