The Government will aim to beef up its post-Brexit relationship with Britain by appointing the most senior civil servant in the country as ambassador.
Secretary general in the Department of An Taoiseach, Martin Fraser, will be appointed Irish ambassador to Britain in 2022 in a rejig that will see the current US ambassador's term come to an end.
Geraldine Byrne-Nason will, in 2022, replace Dan Mulhall as the ambassador of Ireland to the US and vacate her role as ambassador to the UN, which will be filled by Fergal Mythen, currently director general of the Ireland, Britain, and Americas division in Department of Foreign Affairs.
The current British ambassador, Adrian O'Neill, will stay on until 2022, with secretary general in the Department of Foreign Affairs, Niall Burgess, set to take up a new role as ambassador of Ireland to France.
Ambassador Patricia O’Brien will be appointed ambassador to Italy, replacing Colm Ó Floinn.
Deputy-secretary general Brendan Rogers will also be appointed Irish ambassador to the Netherlands, replacing Kevin Kelly.
Elsewhere at Cabinet, the Government agreed a €136bn review of the National Development Programme (NDP).
Public Expenditure Minister Michael McGrath received agreement for the 10-year capital investment plan, which is €45bn more than the existing NDP, an increase of 49%.
When investment from the commercial semi-State companies and other State bodies is included, the total investment will exceed €165bn across the decade.
It is understood that the plans which set out the allocation to individual departments for the next five years and will form the basis of the new plan will be officially launched by Government in September.
A core capital budget of €11.1bn is being earmarked, a further increase from the €9.8bn allocation in the current year.
Reforms are also being proposed to ensure value for money in government procurement processes.
The Cabinet has also agreed to commence the formal procurement process for a new Coast Guard aviation service next October.
The service is currently contracted to CHC Ireland and may be extended up to June 2025 at the latest.
The business case brought to Government set out the strategic case for a new service including the potential for the Air Corps to provide an element of the service as a “hybrid” option alongside another civil operator.
Transport Minister Eamon Ryan said that the service was "costly" but important.
The Cabinet also agreed the appointment of former children's minister Katherine Zappone as a special envoy on freedom of opinion and expression.
A statement said that "this appointment will provide enhanced capacity for engagement on Irish human rights priorities".