The Leader of the House of Commons told Sky News she wanted to see a “level playing field” between those from the EU and the rest of the world once the UK leaves the EU.
Her comments come amid reports a key Cabinet sub-committee is considering this as a post-Brexit option for the UK’s new immigration system.
“It is right that once we have left the EU we are back in change of our immigration rules again,” Ms Leadsom said.
“I would certainly like to see a level playing field for all the people around the world, the brightest and the best, to make a contribution to the UK.
“To have a level playing field so they will all have an equal chance of coming here to make their life here and contribute to our society and our economy.”
The Tory minister’s remarks follow a report in The Times newspaper that Theresa May’s top Brexit adviser, senior civil servant Olly Robbins, proposed two post-Brexit immigration systems at this week’s meeting of the Cabinet sub-committee.
It has been claimed the system offering no preferential treatment for EU migrants found favour with ministers.
Ms Leadsom, who challenged Mrs May for the Conservative leadership in 2016, told Sky News she thought the Prime Minister was doing a “superb job of balancing very strongly held views” on the Tory benches and across the House of Commons.
She also implored her party colleagues to get behind the Prime Minister after a febrile start to the year.
“The Prime Minister is treading that fine line doing a great job and showing a huge commitment to it and I sincerely hope that all of the party continues to support her in that role,” Ms Leadsom said.
The Cabinet discussions on post-Brexit immigration systems come as the Government postponed plans for an immigration bill until the autumn, prompting a backlash from business and MPs.
The bill had been pencilled to come to the House of Commons in January, with a white paper originally promised last summer.
It will now not be released until after a transition deal with the EU is agreed, pencilled in for March.
Yvette Cooper, chair of the House of Commons’ Home Affairs Select Committee, described the situation as a “shambles” in an urgent question in Parliament this week.
“We know that the Prime Minister wants people arriving after March 2019 to be treated differently, but we have no idea how,” said the former shadow home secretary.
“It is just not good enough keeping Parliament in the dark in this way.”
Ms Cooper added: “At best, ministers are cutting Parliament and the public out of the crucial debate about the future of our country.
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“At worst, they seem to be stuck in negotiations without having agreed, even among themselves, what they want to achieve out of them.”
In response, immigration minister Caroline Nokes said an immigration white paper would be published “in the coming months”.