The research, which was conducted in collaboration with Centre for Economics and Business Research (CEBR), found that contributions to the economy will grow by 11% between 2015 to 2020.

London contributed the most (£149bn) in 2015, followed by Manchester and Birmingham (£12bn and £6bn respectively).

London will also see the highest increase in SMEs, rising from 444,880 in 2015 to 534,035 by 2020.

Mark Sismey-Durrant, chief executive at Hampshire Trust Bank, said: “Our report demonstrates the critical importance of SMEs as the engine room of the economy.

“Their sizeable contribution to the fortunes of the UK economy – growing to 27% of total business contribution by 2020 – cannot be ignored.

“As the government prepares for the first Autumn Statement following the decision to leave the EU, I urge them to keep the spotlight on smaller companies by creating conditions which will support their continued growth.”

Nina Skero, managing economist at CEBR, said: “This study demonstrates there is a positive story to be told about the UK’s SMEs and it is encouraging to see such strong growth being mirrored outside of the capital.

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“We expect the importance of SMEs to the country’s economy to increase in the coming years and hope this research will inspire business leaders across the UK to invest in their growth strategies.”

The top 10 UK cities by SME contribution to the UK economy: