London pre-open: Stocks to extend drop as Greek crisis deepens

UK stocks are set to drop further on Tuesday morning after finishing at a five-month low the previous session with Greece set to default on a debt repayment to the IMF.After failing to secure a funding deal with creditors, Athens has effectively ran out of time to come up with the cash to repay the IMF €1.6bn by the 23:00 deadline on Tuesday evening.The government has called a referendum on 5 July and has urged the public to vote against creditors' demands in an effort to help it negotiate a better bailout deal. In the meantime, banks will remain closed until after the vote.City sources predict the FTSE 100 will open 30 points lower than Monday's close of 6,620.48, which was its lowest finish since 20 January.Night dealer Jonathan Sudaria from London Capital Group said the negative open comes "as traders don't know what to make of the Greek crisis"."With only hours to go before Greece defaults on the IMF and the growing support for the 'no' vote, a full on ejection from Europe is a scarily possible reality," he said.Tuesday is set to be a busy session in terms of economic data, with the final estimate of UK first-quarter GDP on tap in morning trade, along with figures on UK business investment, the UK current account, the UK index of services and the Lloyds business baromoter.In terms of overseas data, the following key economic indicators will be released: German retail sales, Eurozone unemployment, Eurozone inflation, Canadian GDP, US home prices and US consumer confidence.Stocks to watchA 30% rise in new customer numbers in the first half of the year helped online grocery company Ocado drive robust growth in revenue and operating profits despite the fierce industry competition. Revenues swelled 18.2% to £507.7m in the 24 weeks to 17 May, with earnings before interest, tax, depreciation and amortisation increased by 11.4% to £38m.Kier Group said on Tuesday that the underlying trading performance for all four of its divisions for the year to 30 June 2015 has remained in line with management's expectations. Following the completion of the acquisition of MRBL Ltd (Mouchel) on 8 June, and as a result of continued underlying organic growth, the total order book for the enlarged group has been maintained at £9.3bn at 31 May, excluding potential further renewals and extensions valued at up to £2bn.Rio Tinto will be in focus after a report in the Financial Times said that Xstrata's former boss Mick Davis was in "serious" talks about buying some of Rio's Australian coal assets.