Meryl Streep made an English couple's wedding day all the more special by applauding the newlyweds while dressed as former UK Prime Minister Margaret Thatcher.

Freya and Graham McAnally had booked to have their nuptials at Manchester Town Hall in the north of England, and were stunned to find The Iron Lady crew shooting scenes in the building, which has similar architecture to the Houses of Parliament in London.

And the pair couldn't believe their eyes when they stepped out of the registry office to find Streep in her Thatcher finery smiling and applauding.

"It was all very surreal - Meryl Streep was standing there dressed as Margaret Thatcher. It almost feels like it didn't happen,'' said Freya.

"I thought it was amazing, the last thing you expect is an A-List celebrity at your wedding.''

And the generous actress made sure the pair's nuptials got off to a great start by gifting them with signed photos, champagne, flowers, a glass vase and a copy of the film's call sheet for the day.

"They went above and beyond what they had to - it was lovely,'' said Graham.

- AAP