Italian rugby chiefs were celebrating Thursday after reaching an agreement on the continuation of two teams in the Celtic League for the next four years.

There had been reports that amid all the uncertainty over the future of the European Cup and with leading Welsh clubs contemplating an alliance with their English Premiership counterparts, that the Italians planned to withdraw their leading clubs Zebre and Treviso into a domestic national championship.

But the Celtic League, which now acts as a 'domestic' tournament for top sides in Scotland, Ireland, Wales and Italy, announced Thursday that the Italian Rugby Federation (FIR) would become an equal partner in Celtic Rugby from July 1, and that two Italian teams would take part for the next four years.

FIR president Alfredo Gavazzi hailed the news as a "huge victory".

"An agreement for Italy to have equal shareholding rights with two teams in the Celtic League as of 2014 has been reached," said an FIR statement.

The FIR also managed to negotiate a huge reduction, by more than two-thirds, of the three-million euros ($4.16m) fee it paid to have two franchises in the league.

"The three million euros fee has been reduced to less than a third... it's a huge victory," said Gavazzi, who has also asked for financial help from the International Board.

Treviso announced last month they would be pulling out of the Celtic League and taking part in a domestic competition next season.

While struggling Parma-based, but federation-run Zebre (Zebras) will continue in the same form -- having been run independently as Aironi for two seasons before becoming Zebre at the start of last season -- it means the second Italian representative is likely to undergo a make-over.

The second franchise is likely to be made up by a collaboration between Venetian teams and will probably take on a locally-relevant name.

On the teams, Gavazzi added: "One will be the north-west franchise, the Zebre, while the other will be from the north-east, and be called Treviso or Dogi (Doges)."

The FIR is expected to officialise the names of the teams in the next fortnight.

However, an agreement ratifying this proposal has still to be signed by all four national unions involved.

A statement issued by Celtic Rugby on Thursday said: "A constructive meeting took place on Tuesday in London between FIR and the Celtic Rugby Unions (Scottish Rugby Union, Irish Rugby Football Union, Welsh Rugby Union).

"The meeting was successful and an agreement was reached for FIR to join Celtic Rugby as an equal partner from July 1st, 2014.

"The terms of participation of two Italian teams were agreed upon. Under the new agreement, FIR will ensure the participation of two Italian teams for the next four years in the competition which is currently known as the RaboDirect PRO12.

"The agreement between FIR, SRU, WRU and IRFU will be officially signed in due course."