The World Heritage Site bid for the twin Anglo-Saxon monastery of Wearmouth-Jarrow has been deferred.
The monastery, comprising St Peter's Church in Wearmouth and St Paul's Church, Jarrow, was the UK's nomination for the status, in 2010.
Originally scheduled for submission in February 2010, it will now be submitted in February 2011.
The team behind the bid said the deferral will enable it to strengthen the submission for the site.
A spokeswoman for Sunderland City Council said the team wanted to create a "visitor experience" at the church sites, using funding from One North East.
She said changes to the sites could include signage and interpretation display boards, which would inform visitors of the sites' historical importance.
The deferral has been backed by the Department for Culture, Media and Sport who work with candidate sites. A nomination document and management plan was to be submitted to UNESCO (United Nations Educational, Scientific and Cultural Organisation) by the UK Government.
Rt Rev Mark Bryant, Bishop of Jarrow and chair of the Wearmouth-Jarrow Partnership said: "In recent months we have been overwhelmed with the support of people from the region and further afield, and we now have time to further improve our submission documents, which will give Wearmouth-Jarrow the best possible chance for a successful inscription."
Extensive public consultation between April and June 2009 saw a total of 8194 responses, with 96% of people supporting the nomination.
Wearmouth-Jarrow was a major international centre of learning and culture in the 7th and 8th Centuries.
Parts of the 7th Century buildings still stand on both sites and it was home of Bede, who was one of the most influential figures in contemporary culture.