UK stock markets were expected to be unchanged on Wednesday morning with investors treading cautiously amid developments in Greece ahead of the long weekend.City sources predict the FTSE 100 will open broadly flat on Wednesday's close of 6,809.50. UK markets will be closed on Friday and Monday for the Easter break.Athens submitted a new proposal of economic reforms overnight "which is more specific and quantified", according to the Greek finance ministry. The 26-page document suggests that Greece could raise as much as €6bn this year as it looks to unlock €7.2bn in bailout funds before it runs out of money.However, EU officials claimed that the new list still needs more work and a deal is not expected before the next meeting of Eurozone finance ministers on 24 April.Analysts at Barclays said the new list "represents a clear step in the right direction in our view" for Greece."However, we do not think this document represents the last iteration of reform proposals exchanged by Athens and Brussels, given that it contains some elements that are likely to be further revised."Stocks to watchIn the fourth quarter Marks & Spencer delivered its first growth from clothing and general merchandise for 14 quarters, with like-for-like sales up 0.7%. Helped by heavy investment in its website finally paying off and food delivering another strong performance, group sales rose 1.9% in the 13 weeks to 28 March.Guinness and Smirnoff maker Diageo is buying out its joint venture (JV) partner in a traditional sorghum beer business in South Africa. The 50:50 JV, which owns the United National Breweries, was set up in January 2013 with Pestello Investments. Diageo has now decided to acquire Pestello's 50% stake for an initial payment of $22m and a potential earn-out payment of up to $14m.