Jeremy Corbyn is determined to resist pressure to spell out in more detail what Brexit settlement Labour would support, despite a series of comments in recent days suggesting the party is edging closer to advocating continued single market membership.

The shadow cabinet will discuss Brexit at its weekly meeting on Tuesday, the first since Theresa May clinched the agreement of European commission president, Jean-Claude Juncker, to move on to the second phase of the negotiations.

Several frontbenchers, including the shadow Brexit secretary, Keir Starmer, and the shadow chancellor, John McDonnell, have appeared to signal a shift towards arguing for the closest possible future relationship with the EU.

Launching a report on rebalancing public investment, McDonnell said the UK could remain part of a “reformed single market” and stressed that Labour mustI gave in Florence. Meanwhile, the Labour party has had 12 different Brexit plans. In fact, the right hon gentleman has had so many Brexit plans he cannot even reach alignment with himself.”

The Liberal Democrat leader, Vince Cable, even suggested the prime minister should ask the Labour leader to join her negotiating team since they agreed about leaving the single market and the customs union. But Corbyn said the first phase of Brexit talks had been characterised by “posturing, delays and disarray”.