LONDON (Reuters) -Britain's Office for Budget Responsibility will carry out one full fiscal forecast a year instead of the current two, according to its outlook unexpectedly published on Wednesday ahead of finance minister Rachel Reeves delivering her budget.

The OBR has so far published two assessments annually to accompany the government's spring and autumn fiscal statements. They provide detailed economic projections and whether the finance minister is on course to meet targets for the public finances.

The International Monetary Fund had recommended that the OBR assess the government's progress towards its fiscal rules only once a year to reduce speculation about what measures might be needed to stay on track.

Reeves has previously said that the OBR's two full forecasts a year made it harder to have a single major fiscal event.

(Reporting by Muvija M, writing by Sam Tabahriti; editing by William James)