The BRICS group of emerging market countries is moving forward with plans for expansion, with an announcement expected at the bloc's annual summit in Kazan, Russia, this October.

However, Venezuela's inclusion in the next wave of expansion appears uncertain, according to Brazilian officials familiar with discussions at the United Nations last week, Bloomberg has reported.

The officials, speaking on condition of anonymity, said Venezuela was not included on a preliminary list of prospective invitees circulated by Russia among BRICS members during the UN General Assembly in New York.

Russia, which currently holds the BRICS chairmanship, is seeking consensus on which countries to invite as it prepares to host the bloc's summit from October 22 to 24.

Belarusian Foreign Minister Maxim Ryzhenkov, speaking on the sidelines of the UN General Assembly, suggested that at least ten new members could be added in this round of expansion.

The BRICS group, which currently includes Brazil, Russia, India, China, and South Africa, added Iran, Ethiopia, the United Arab Emirates, and Egypt as new members in January.

Brazilian officials cautioned that expansion talks have so far occurred only among diplomats and foreign affairs ministers, and final decisions have not been made.

Caracas' potential inclusion has reportedly caused discomfort in Brazil, following disputed elections in Venezuela in July that have strained relations between Venezuelan President Nicolas Maduro and Brazilian President Luiz Inacio Lula da Silva. Brazil, along with many other regional and international actors, has repeatedly called for Venezuelan's National Electoral Council (CNE) to publish detailed voting records to back up the official results which saw the incumbent re-elected for another six-year term, but the Maduro-aligned body has refused to do so.

Brazilian officials have also reportedly vetoed the invitation of Nicaragua, a close Russian ally ruled by President Daniel Ortega, with whom Lula fell out earlier this year leading to the severance of diplomatic ties.

In August, Venezuela's Foreign Minister Yván Gil announced that the country was actively participating in all BRICS group meetings and was "merely awaiting formal admission into the bloc."

President Maduro warned the United States and its allies that he might transfer oil and gas blocks to BRICS countries, citing increased pressure from Washington over the recent election, which many view as marred by fraud.

The next wave of expansion is expected to add countries as partner nations rather than full members, according to a Russian official familiar with the plans.

BRICS nations are also working on developing a joint payment and settlement framework for intra-group trade, as stated by Russian President Vladimir Putin at a recent bloc meeting.

BRICS countries currently represent about 46% of the world's population and over 36% of global GDP, according to recent estimates by global financial institutions.