A SENIOR minister is pushing the Prime Minister to spend the UK’s overseas aid budget on successors to the Royal Yacht Britannia.

Paymaster General Penny Mordaunt wants Boris Johnson to deliver on his pledge to shake up the aid budget with the purchase of two new ships to replace the royal yacht.

The former international development and defence secretary told the Tory leader that it would be within Overseas Development Assistance (ODA) rules to make the purchase.

Mordaunt wrote to Johnson with her plans for "the concept of highly flexible vessels that could be part funded from the ODA budget in partnership with private, research, commercial and charitable funds".

READ MORE: Boris Johnson has put final nail in the coffin for ethical foreign policy

She went on: "We know that industry would also support [it] as would a growing coalition of commercial and trade ventures, research organisations, shipbuilders and ship support companies, maritime training organisations and medical and health projects.

"These vessels have been rightly seen as a successor to the Royal Yacht Britannia. Given the level of interest it may be possible to generate income from the vessels."

The MP said the ships could be a “cost-effective” place for royal family figures to stay on visits.

She added: "Now is the time to be bold and creative. To think what we actually need and how we can deliver on it with a reduced budget."

The MP’s calls come after it emerged the Department for International Development would be closed and merged with the Foreign Office, sparking concerns for 600 jobs at the department’s East Kilbride base.

Johnson’s plans have been controversial, with three former prime ministers speaking out against them. He was accused of jeopardising the UK’s standing in the world.

Mordaunt’s letter also follows news that the Prime Minister’s plane is to be repainted from grey into Union flag colours at a cost of nearly £1 million.

A UK Government spokesman said: "The merger of Dfidand FCO will ensure our aid and foreign policy are aligned, and that decisions on aid spending are made in line with our international objectives.

"We will continue to look at how our aid budget can be spent most effectively and in our national interest, including through the Integrated Review – which will report in the autumn and inform the priorities of the new department."