Economic calendar: Quadruple witching day in the US

• European markets seen opening lower

• Quadruple witching day in the United States

• UK retail sales miss expectations

Futures markets point to a slightly lower opening of the European stock markets today. Economic calendar for today is almost empty. UK retail sales data for May was released at 7:00 am BST and turned out to be a disappointment. Market expected a 1.5% MoM increase while the data showed 1.4% MoM drop. Core retail sales were 2.1% MoM lower (exp. +1.5% MoM). GBP took a small hit following the release. Investors will be offered a speech from Fed's Kashkari in the later part of the day.

Another point to keep in mind is that today is the so-called "quadruple witching day". Term relates to a situation when a number of US derivatives (index futures, stock futures, index options and stock options) expire on the same day. It may potentially facilitate some volatility spikes during the final hour of the US cash session (8-9 pm BST).

9:00 am BST - Poland, labour market report for May.

• Employment change. Expected: 2.4% YoY. Previous: 9.9% YoY

• Wage growth. Expected: 2.4% YoY. Previous: 0.9% YoY

Central bankers' speeches

• 6:30 pm BST - Fed Kashkari