OSLO, Feb 17 (Reuters) - Oil and gas firms in Norway have raised their investment budgets for 2021 in recent months, but still plan to spend less than last year and also expect a decline in 2022, an industry survey by the national statistics office (SSB) showed on Wednesday.

Investment in the country's main economic sector is now projected at 173.6 billion Norwegian crowns ($20.5 billion) this year, up from a forecast of 166.3 billion crowns in November, lagging last year's 179.3 billion, SSB said.

For 2022, the survey's initial forecast of 138 billion crowns was 8.9% lower than the similar predictions for 2021 a year ago, SSB said.

($1 = 8.4731 Norwegian crowns) (Reporting by Terje Solsvik, editing by Nora Buli)