Oil analysts are putting down markers on the Organisation of the Petroleum Exporting Countries' (Opec) meeting on November 27, when members will consider whether to cut output to shore up prices.

Opec members Iran and Venezuela have urged fellow crude producers to support oil prices, which have sunk more than 30 per cent since June to four-year lows. Kuwait and Iran have said an output reduction is unlikely, while Libya, Venezuela and Ecuador have called for Opec to cut production.

The following is a list of comments from brokerages and banks on what they expect from the meeting:

Bank of America Merrill: May go for a ceiling cut of just 0.5 million barrels per day "Should prices average $76 per barrel (current forward), shale oil growth would stand at just 500,000 barrels per day next year, while $60 would leave production flat."

"A $50 per barrel oil price band may serve Saudi interests better than a tight $20 per barrel band. After all, Saudi can ramp output up or down within three months, while it takes shale players 6-12 months to react to rising or falling prices," it stated.

Eurasia Group: Agreement on a cut will not materialise "With the upcoming November 27 Opec ministerial meeting in Vienna only a week away, it is increasingly likely that an agreement on a 'headline' production cut will not materialise, despite the current flurry of pre-meeting diplomacy.

The only thing Opec ministers are likely to be able to reach unanimity on is a statement containing language about making a commitment to "strict compliance" with the existing 30 million bpd group production ceiling."

Morgan Stanley: Several potential scenarios are likely. 1) A reduction in the quota, likely to 29.5 million barrels per day, dismissing some price war fears and sparking a rally (33 per cent probability). 2) Unchanged quota, but talk of stricter compliance would likely cause a modest rally (33 per cent). 3) No action given financial nature of last leg of the selloff. Oil will likely fall on concerns over a new paradigm but less than the upside in a cut (33 per cent).

Capital Economics: Unlikely to cut by a meaningful amount "We think that any cut in the cartel's production target will simply be as a response to lower demand for its oil, rather than a concerted attempt to push up prices. We therefore do not expect the cartel to be able to prevent the price of a barrel of Brent from falling to $70 by the end of 2016, even if this is below Opec's current comfort zone."

Goldman Sachs: Increased likelihood of a cut, but not a large one. "With the decline in prices, the likelihood of Opec announcing a production cut has increased ... We nonetheless still believe that a large cut in excess of 0.5 million barrels per day (bpd) is not in the organisation's interest.

First, large production cuts would likely support US production growth, requiring further cuts in 2016 and beyond. Second, a large cut would be difficult to implement given some of Opec members' financing needs (Libya, Iran, Iraq, and Venezuela).

BNP Paribas: A cut of 1 million to 1.5 million bpd. "We do not believe Saudi Arabia is seeking to shut down the marginal higher cost producer (US shale oil) and will therefore adjust its production to support prices," said the expert.

"The lack of communication regarding future oil output and the apparent lack of concern at current oil price levels by Saudi Arabia is most likely intended to incentivise fellow Opec members to join in a collective cut in the cartel's supply," it added.

JP Morgan: No agreement. "In the short term, we now expect Opec to be unable to reach an agreement in its end-November meeting. Consequently, the prospect of oil inventories increasing substantially in excess of seasonal norms will likely pressure prices," it stated.

Societe Generale: Cut of 1 to 1.5 million bpd (60 to 70 percent probability). "Our central scenario is for Opec to decide to cut production by 1-1.5 million barrels per day at the key meeting, there is a 30-40 per cent chance that production would be kept unchanged," said the bank.

Deutsche Bank: No cut. "We do not see a co-ordinated cut in production for three reasons, the first of which is the new Saudi strategic positioning ... (Statements from Saudi officials indicate that they are prepared to tolerate a period of lower pricing in order to stimulate discipline across a broader cross-section of supply both in other Opec members as well as non-Opec producers).

The second reason is that there has been a diversity of opinion expressed in public statements by oil ministers, suggesting that an agreement may be difficult. The final reason why a cut may be unlikely is that currently quotas for individual members have not been in place since 2007.

As a result, this means that any co-ordinated cut (shared amongst OPEC members) would first require a re-establishment of these country breakdowns, which itself could be contentious and thereby introduce delays."

Santander: Cut of 500,000 bpd through compliance "I think Opec will call for 'quota discipline' essentially taking 0.5m bpd out of world oil markets by mid-2015 if this is done. No formal cuts versus agreed quotas though."-Reuters