Rugby union’s powerbrokers have reached a staging agreement for the Nations Championship that will mean the first set of finals are held in London and Qatar, before a possible move to the United States, in a major global expansion of the sport.

Under radical plans expected to be signed off later this month, Twickenham would stage the first Nations Championship final in 2026, before the biennial six-match series moves to Qatar two years later, with a further option to go to America in 2030.

Qatar had hoped to stage the first four Nations Championship finals and were granted exclusive negotiating rights by the 12 biggest unions this summer after offering ­guaranteed returns of £800m, but their bid was blocked by the Irish and French unions due to uncertainty over attendances and concerns over the country’s human rights record.

The new blueprint disclosed is seen as a compromise, with staging the first final at Twickenham regarded as a crucial concession to those worried the sport is being sold to the highest bidder. The Six Nations and southern hemisphere unions are understood to be close to signing a heads-of-term agreement on an initial four-year contract that will confirm the 2026 and 2028 hosts as London and Qatar respectively.

There is also an option for a second four-year deal that would take the 2030 finals to the USA before returning to Qatar two years later, which can be triggered if certain commercial and media rights targets are met. The Qatar games would all take place in Doha, while USA Rugby would run a tender process to determine the 2030 hosts with the MetLife Stadium in New York regarded as an early ­frontrunner to get the final.

The proposed new deal would enable the unions to cash in on some of the riches being offered by Qatar, while giving the first finals a safer launch event in London, as well as the opportunity for a major promotional push before the Rugby World Cup being staged in the United States in 2031. The ­Middle East and USA are seen as the two major growth markets for the sport with the ­women’s World Cup also due to be held in America in 2033.

The financial returns on offer from Qatar are seen as too great for rugby to ignore, particularly by the southern hemisphere unions, with New Zealand, South Africa and Australia posting annual losses totalling tens of millions of pounds in recent years. Even the Rugby Football Union has financial concerns after agreeing to fund 25 enhanced central contracts for England’s male players, with the redundancies of more than 40 staff being announced last month despite the governing body agreeing a £100m naming-rights deal for Twickenham with insurance company Allianz a few weeks earlier.

It is understood that the financial projections for staging the Nations Championship finals in Qatar are three times greater than those for London. Rotating the host venue would provide the additional income required to fund the finals as a ­playoff series involving 12 teams in the top division of the biennial Championship. The Six Nations teams will play three matches away and three at home against the Sanzaar nations and two others – expected to be Japan and Fiji – in July and November to determine the playoff lineups.

The sixth-ranked European team after the six group matches would play their equivalent from the southern hemisphere, with fifth facing fifth and so on, leading to a grand final to determine the championship winners. For the first event in London in 2026 Twickenham, the Tottenham Hotspur Stadium and the Stoop are understood to be in the running to host matches as, given the range of teams involved, a variety of stadiums of differing sizes will be required.

Negotiations have been continuing for several months, but unions are pushing to get it signed by the end of October so they can begin the process of selling broadcast rights.

The sale of TV rights has proved difficult for rugby in recent years so the unions want as much time as possible to conclude a deal, particularly as they will be pitching a new competition to broadcasters.

The Six Nations, which will operate the new championship alongside its southern hemisphere equivalent, Sanzaar, declined to comment.