The opening of a new bridge over the Hudson River has been delayed just one day after its opening ceremony due to a 'potentially dangerous situation'.

On Friday, Hilary Clinton joined New York Governor Andrew Cuomo to officially open the second span of the new Mario M Cuomo Bridge - which was named after the current governor's late father.

But its scheduled Saturday opening has been since pushed back after a piece of the bridge it is replacing became destabilized and threatened to fall, officials said.

The new $4billion bridge connects Westchester and Rockland counties 30 miles north of New York City and is replacing the old Tappan Zee Bridge, which opened in 1955, and is in the process of being demolished.

Hilary Clinton joined current New York Governor Andrew Cuomo for a ribbon cutting ceremony for the bridge named after his father Friday

The opening has been pushed back after a piece of the bridge its replacing, the Tappan Zee, became destabilized and threatened to fall

The Mario M Cuomo Bridge over the Hudson River was to open Saturday, named after New York's former governor

The New York State Thruway Authority says 'a potentially dangerous situation' developed Friday night when a piece of the old Tappan Zee Bridge between became destabilized during the ongoing process of disassembly.

'Given its proximity to the new completed span, out of an abundance of caution, motorists will remain in the current traffic configuration until a thorough evaluation by Tappan Zee Constructors is complete,' said Matthew J. Driscoll, head of the New York State Thruway Authority.

The closure has been met with criticism by Cuomo's rivals, including candidate Cynthia Nixon, who says the ceremony was timed for positive coverage before the primaries

'The second span is finished and ready to open to traffic as soon as the Thruway Authority is assured there is no risk to the new span,' he added.

The issue came just hours after Democratic governor Cuomo held a grand opening ceremony for the new bridge span and was joined by former presidential candidate Hilary Clinton.

Cuomo said Friday that the new bridge 'shows the world that we're capable of dreaming big and delivering results for the people of this state.'

However, Cuomo's rivals claim the timing of the ribbon cutting ceremony was a stunt as it came just days before the primaries.

His primary opponent, actress Cynthia Nixon, condemned Cuomo's bridge opening as a dangerous ploy for positive coverage before the elections.

'A ribbon-cutting ceremony should not have been held if the bridge span was not yet safe,' Nixon, said in a statement Saturday. 'There are real, reasonable questions about whether this bridge span opening was accelerated to aid the governor's campaign.'

'Safety has to come first,' Nixon reiterated in a tweet Saturday.' The Governor should not rush to cut the ribbon on a bridge if it's not yet safe.

'There are real, reasonable questions about whether this bridge span opening was accelerated to aid Governor Cuomo's campaign.'

Nixon speculates the ceremony was a ploy right before the primary elections

The new $4billion bridge connects Westchester and Rockland counties 30 miles north of New York City

Nixon used the hashtag '#CuomosBridgegate' as spin off former New Jersey Governor Chris Christie's Bridgegate scandal in which lanes of the George Washington Bridge were closed, causing extreme delays.

The new bridge's first span opened last year.

Cuomo, who is also considered a potential Democratic presidential candidate in 2020, has been a frequent critic of Trump, a native New Yorker who defeated Clinton in the 2016 election.

During a speech made before the ceremonial ribbon cutting, Clinton lauded state officials who guided the bridge's construction and the 7,000 workers who built the twin 3.1-mile-long spans.

'It is time for the United States of America to take another look at what's getting done here in New York and follow this example,' she said.

Cuomo said the new bridge, the nation's largest infrastructure project, has 'national significance' because it stands as an example of what the nation can accomplish despite the current deep political rifts.

'This bridge restores confidence in ourselves,' he said. 'At a time when the president is obsessed with his singular goal of building a wall, this bridge stands in defiant opposition.'