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TUNIS, Oct 14 (Reuters) - Tunisia expects to seek $2.78 billion in foreign loans next year - nearly double its 2016 external financing needs - to help cover a 2017 fiscal deficit expected at 5.4 percent of GDP, according to the 2017 budget published by state news agency TAP.

Last year's budget anticipated foreign lending for 2016 at $1.45 billion.

Prime Minister Youssef Chahed has said he wants to introduce reforms including new taxes, subsidy reductions and a freeze on public sector wage increases to bolster fiscal revenues and control the deficit.

The powerful UGTT and other unions are opposing some of what they see as austerity measures that will hit people's spending power. The leftist Popular Front opposition party has organised a march against austerity for Friday.

The cabinet on Friday approved a 2017 budget with spending pegged at 32.7 billion Tunisian dinars ($14.8 billion), a 12 percent increase, TAP reported.

The government expects a 15.7 percent increase in fiscal receipts, reaching 21.8 billion dinars compared with 18.8 billion expected in 2016, TAP said.

The budget sees 2017 economic growth at 2.3 percent versus a forecast of 1.5 percent for this year. The budget deficit is expected to narrow from an expected 6.5 percent of gross domestic product this year, TAP said.

($1 = 2.2100 Tunisian dinars)

(Reporting by Tarek Amara; writing by Patrick Markey; editing by John Stonestreet) ((pat.markey@thomsonreuters.com; +213-661-692993; Reuters Messaging: pat.markey.thomsonreuters.com@reuters.net))