Roker Pier could be closed during restoration work after a wave of vandalism and theft.
Council chiefs are also looking at banning anglers from the pier because of recurring problems.
The pier was reopened to the public in November, after an £850,000 programme of repairs.
Work to restore the pier’s lighthouse is still going on.
But both the lighthouse itself and the contractors’ compound have been targeted, with fixtures and fittings vandalised, arson attempts and tools being stolen.
Members of the public have also been putting themselves in danger by climbing on works scaffolding.
In the latest incident last week, the lighthouse was broken into, when tools were stolen and the site damaged.
Northumbria Police Neighbourhood Inspector Tony Carty said:” Local officers are aware of the issues and have increased patrols in the area. Officers from the Neighbourhood police teams have also provided crime prevention advice on the site and made suggestions around how security could be improved.”
Coun John Kelly is the city council’s Portfolio Holder for Public Health, Wellness and Culture: “There appears to be a tiny minority of the public, some who claim to use the pier for sea fishing, who are determined to spoil this restoration project,” he said.
“There have been more than a dozen incidents of theft, vandalism and trespass during the works along with threats and verbal abuse to the contractors.
“These problems are wasting both council tax payer’s money and the grant that came through the Heritage Lottery Fund causing serious delays to the restoration work.
“The incidents have all been logged with the police and we are now considering whether or not the pier should be closed to the public until the works are complete and possibly even introducing a by-law to stop fishing altogether.
“The pier is one of the city’s best-loved landmarks and is there for the enjoyment of everyone, so closing the pier for any amount of time will be a sad step we have been forced to take.
“It would also badly affect local businesses at a time of year when they rely on an increase in trade with more people visiting the pier and seafront.”
Secretary of the Northern Federation of Sea Angling Clubs Andy Rutherford added: “I’m sure the vast majority of responsible anglers who use the pier will share the council’s concern and understandable anger at the actions of these mindless idiots who threaten to spoil things for the rest of us.
“I’d hope that we can all work together to prevent this kind of irresponsible and anti-social behaviour from happening again, so Roker Pier can remain open for everyone to enjoy while restoration work continues.”
Roker Pier and the lighthouse are Grade II-listed and restoration work is being carried out by specialist contractor William Anelay, from North Yorkshire.
Spokesperson Sam Weller said: “One of our contractors is devastated because some of the tools he has had stolen are ones he has been using for more than 30 years.
“I’m sure there are many other people out there, who take great pride in their work and skills, who would be equally upset if the ‘tools of their trade’ were stolen.”