Concern about the way the pubcos operate is growing among politicians, according to a GMB official.
Kathleen Walker Shaw, GMB's European officer, told The Publican that she and GMB officials had met with a number of "sympathetic" MEPs in Brussels today - as part of an ongoing bid to prove the beer tie is anti-competitive.
Shaw and Fair Pint campaigners initially met with Labour MEP Catherine Stihler this morning - and another meeting involving CAMRA is due to take place this afternoon.
Under current EU regulations the beer tie is exempt from EC Treaty competition rules - but this "block exemption" is currently up for review.
"We have been pleasantly pleased at the support we are now getting at a political level and we are looking to use that," said Shaw.
"There has been an offer made to raise the concerns with the EC and the UK government to try to get them to take action to prevent these practices."
This afternoon, the campaigners are expected to meet with an EU Commission official for Consumer Affairs, who deals with block exemption issues.
Paul Maloney, GMB national officer said: "These meetings today in Brussels are important and form part of the GMB 'all fronts at all times' strategy to secure a fair deal for the UK's tied pub tenants."