The newly formed Independent Group will provide a “great opportunity” to boost a political centre-ground which is “desperate to grow”, according to Willie Rennie.
Speaking on the BBC’s Good Morning Scotland on Friday ahead of his party’s conference, Mr Rennie praised the decision of the eight Labour and three Conservative MPs to defect.
And the Liberal Democrat leader said that he would be prepared to work with the new group to help progress a moderate agenda.
“I think they’re quite courageous, I’m full of admiration that they’ve taken the step,” said Mr Rennie.
“I think it’s early days but I’m keen to cooperate with like-minded people and try and increase the force of moderation in British politics, which the Liberal Democrats represent.
“Some of them have been there for quite some time so, actually, taking the step to go as independent is quite something in itself.
“But there’s no doubt that there’s quite a lot of common ground between us - they’re very much pro-European, they’re very much in favour of investing in public services, the merits of good immigration to the country - all of those issues are common values and policies between us.
“So we’ve got to have further discussions with them, we’ve been discussing with them for some time and in fact, encouraging them to take this step.”
The Liberal Democrat leader also indicated that he would continue to push for holding a People’s Vote over EU membership and said that it was important for moderate MPs to build voters’ trust.
Mr Rennie said: “The potential of the centre-ground vote is really considerable and that’s where we’ve got to try and work together to exploit that vote, give people confidence that it’s worthwhile voting for that centre-ground to make that difference so we can have a new, brighter, progressive form of politics that’s internationalist in its outlook but also in favour of a good economy and good public services.
“That centre-ground there is desperate to grow and we’re determined to contribute towards it”.
Having won 23% of the vote in 2010 and forming a coalition government with the Conservatives, the Liberal Democrats have since lost the majority of their MPs.
Currently, there is an equal number of Liberal Democrat MPs as there are members of the Independent Group, with a total of 11.
Mr Rennie said: “We’re rebuilding from some difficult times in recent years and there’s no doubt we are rebuilding.
“There is a steady growth in our party once again. But this new Independent Group gives us a great opportunity to boost that further forward.
“We’re determined to work with them to try and exploit that, to reach parts of the country that perhaps the Liberal Democrats are not as strong in and I think that’s where the real opportunity is”.