The policing operation to create a tight security around the time of the visit would need a lot officers, Commissioner Sir Bernard Hogan-Howe said.
A spokesman for the force confirmed to getwestlondon : "The Police Commissioner has said Trump's visit could match the figure of £7.5 million used to police the G20 summit in 2009."
Unless a special grant is given by the government, reinforcements would need to be made using taxpayers money in order to conduct the necessary procedures.
Sir Hogan-Howe said: "At the moment, people are concerned there might be lots of protests.
Thousands marched in protests against Prime Minister May's invitation
"We can’t definitely say that there’s going to be huge amounts of problems, but I think it is fair to say that we have got some concerns already.
"No doubt we will put a lot of officers out there and keep people safe and make sure that everything goes well.
"If it’s a few thousand officers then obviously it will cost quite a bit of money."
It comes as MPs vote in Parliament today (February 20) on the state visit after a petition calling for it to be cancelled reached over 1.6 million signatures, with thousands from west London .
Trump's presidency has not come without controversies in London, after thousands staged protests across the country after his inauguration.
Around 100,000 attended the women's march led by the Women's Equality Party , which they said was a protest against the "politics of fear".
Meanwhile, other protests have been held outside the US Embassy against the controversial travel ban which attempted a block on seven Muslim-majority countries travelling to America.
In an interview on Sunday (February 19), Mayor of London Sadiq Khan, who has openly critiqued the executive order made by Trump, said the country "should not be rolling out the red carpet" after the "shameful ban".
However, Prime Minister Theresa May has so far said the visit will not be cancelled.
Keep up to date with the latest news in west London via the free getwestlondon app
You can even set it to receive push notifications for all the breaking news in your area