A right-wing think tank has said it will be “expanding its network” into the Labour Party and will announce one of its peers as a patron in the coming weeks.

Speaking at a Labour Party Conference fringe event in Liverpool, Duncan Simpson, executive director of the Adam Smith Institute (ASI), said it had been interested by some of Labour’s new policies.

A Labour MP has called the announcements “concerning” and said the peer – who is yet to be named – should “think twice” about working with the organisation, which does not declare its UK funders and received the lowest possible transparency rating in openDemocracy’s ‘Who funds you?’ project.

Speaking at the ‘Growing into power?’ event, Simpson said Labour’s planning reform announcement had been looked on positively by the think tank. He did not name the peer it is set to partner with, but said it would be making an announcement in the next few weeks.

Simpson said the think tank was “delighted” to be “expanding its network into the Labour Party much more”.

The ASI, named after the 18th-century Scottish thinker on capitalism, lobbies on issues such as deregulation and lower taxes. It has historic ties to the Conservative Party, influencing policy under Margaret Thatcher, and more recently hiring former chancellor Nadim Zahawi as a director. It is reported to be partly funded by the tobacco industry as well as American climate denial groups.

It is not a breach of the ministerial code to work with lobby groups, but according to the Lords code of conduct, peers must register their links to think tanks whether “financial or non financial”. When working with lobbyists, members must act with “integrity and openness”.

Labour MP Clive Lewis told openDemocracy the relationship raises questions around transparency and lobbying.

“I would question why a Labour peer would want to work with a right-wing organisation that has refused to be transparent about its funding sources. In a democracy, that transparency is critical for accountability in terms of how decision-makers are being influenced,” he said.

“[The peer] should think twice about the organisation they are thinking of signing up to.”

Lewis also said it was worrying that organisations like the ASI were interested in being involved in the Labour Party.

“There are a number of institutions that are now lining up and preparing for the advent of a Labour government,” he said. “They've been very happy throughout the past 13 years, or the past 60 years, to support some of the most right-wing governments we've seen in this country in the post-war period, and they're now hedging their bets and hoping that they can influence the Labour government.

“It does raise questions about why these organisations now feel they're going to get a hearing suddenly, and that is concerning.”

Think tanks often have a presence at party conferences, irrespective of whether they are transparent about funding. This year, the Conservative Party Conference was overrun with fringe events and private drinks hosted by organisations like the Institute for Economic Affairs and Policy Exchange, neither of which declare their funders.

openDemocracy has approached Labour for comment.