The government is likely to compile an extra budget worth around ¥3.5 trillion ($28.5 billion) at the end of this year to help farmers boost their global competitiveness and finance social security measures, sources said Saturday.

Prime Minister Shinzo Abe will instruct ministries to compile the supplementary budget after reviewing the preliminary results Monday of the nation's gross domestic product data for the July-September period.

The extra budget will be bigger than the previous year's ¥3.12 trillion, but the government will use unspent money from the fiscal 2014 budget and tax revenues for this fiscal year to avoid issuing new government bonds, the sources said.

Projects to be financed by the extra budget will be formally decided by mid-December, the sources said.

The government has already started formulating measures to support the agricultural sector following the free trade deal agreed to by Japan and 11 other Pacific Rim nations.

The extra budget will likely help finance projects aimed at enhancing farmers' global competitiveness.

The supplementary budget will also be used to build nursing homes for the elderly and assist those who would otherwise need to leave jobs to care for their family members.

In addition, the government is looking into providing benefits to low-income pensioners, the sources said.

It will also include disaster prevention measures in response to the devastation left by the flooding that hit eastern and northeastern Japan in September, the sources said.

The extra budget will be formed at a time when the government is aiming to turn the primary balance deficit into a surplus by fiscal 2020. Japan's fiscal health is the worst among industrialized nations with public debt at more than 200 percent of nominal GDP.

The government is also considering reducing the issuance of new government bonds in the initial budget for the current fiscal year, the sources said.