However, shares in the company fell as much as 8 percent after 2018 revenues fell short of market expectations, with analysts pointing to a slowdown in underlying growth during the last quarter of the year and a drop in free cash flow.

G4S, which has more than 500,000 employees across 90 countries, has been working to rebuild its reputation after a series of scandals, notably a failure in 2012 to provide enough guards for the Olympic Games in London.

In December, the company said it would look to split off its cash unit, which includes Cash 360 machines operated by retailers and a cash transport business, to create two separate businesses to better focus on their customers and markets.

On Tuesday, G4S said it would continue to consider all options for the unit and declined to give details about potential buyers.

The business accounts for about 15 percent of group revenue and has been struggling with a drop in cash-based transactions in developed markets.

Group revenue rose 1.1 percent to 7.3 billion pounds last year, missing analysts' average forecast of 7.42 billion pounds, according to Refinitiv Eikon data.

That included a 9.3 percent drop at the cash solutions business, in part because the previous year benefited from a large cash technology and services contract in North America.

Analysts at Jefferies, JP Morgan and UBS pointed to a slowdown in fourth-quarter underlying growth to about 1 percent from around 2.5 percent in the first nine months of the year.

UBS and Jefferies also highlighted a bigger than expected 12 percent drop in free cash flow.

However, G4S said sales wins in the second half of 2018 had underpinned a good start to 2019.

At 1100 GMT, its shares were down 4.2 percent at 199.41 pence, the biggest fall on the UK's FTSE-100 index.

G4S said it planned to start the process of separation of the cash unit in the second half of the year. It expects to invest around 20 million pounds in restructuring the unit in 2019 and estimated the costs of the separation review and process would be about 25-50 million pounds.

Full-year adjusted profit before interest, tax and amortisation of 474 million pounds was in line with restated numbers released by the company last Wednesday.

(Reporting by Arathy S Nair in Bengaluru; Additional reporting by Samantha Machado; Editing by David Evans and Mark Potter)

By Arathy S Nair and Pushkala Aripaka