Hillary Clinton visits Armenia on South Caucasus tour

US Secretary of State Hillary Clinton is visiting Armenia at the start of a tour of the South Caucasus.

Her trip comes as a ceasefire between Armenia and Azerbaijan is looking increasingly fragile.

The two former Soviet republics fought a bloody war over the disputed region of Nagorno-Karabakh in the 1990s.

The BBC's Damien McGuinness, in neighbouring Georgia, says it is hoped Mrs Clinton will ease tensions between the two countries.

The region is dependent on US aid so Washington has much influence there, he says.The conflict between Armenia and Azerbaijan erupted as the Soviet Union collapsed and at least 30,000 people were killed by the time a ceasefire was declared in 1994. Since then, a simmering stalemate has prevailed and both sides have reported sporadic breaches of the truce.

Human rights

Both sides have been building up arms in recent months and refusing to compromise. It is hoped Mrs Clinton will at least call on both governments to tone down the rhetoric and hold peace talks.

Human rights groups also want Mrs Clinton to address alleged abuses in the region. Azerbaijan's harsh treatment of government critics has been in the spotlight since it hosted the Eurovision Song Contest in May.

Authorities have dismissed criticism in the international press as Armenian propaganda. However, condemnation from the US Secretary of State will carry more weight, our correspondent adds. Mrs Clinton travels on to Georgia on Tuesday and Azerbaijan on Wednesday.

Diamond Jubilee: Pop royalty to play for Queen

About 12,000 people are expected at Buckingham Palace later for a picnic ahead of a star-studded concert to mark the Queen's Diamond Jubilee.

Sir Paul McCartney, Stevie Wonder and Sir Elton John are among the artists, and Madness will perform on the roof.

The show will end with Queen lighting one of about 4,500 beacons across the world marking her 60-year reign. Beacons in Commonwealth countries including Tonga, Australia and New Zealand have already been lit.

Australia's Prime Minister Julia Gillard lit the beacon at Parliament House in Canberra.

They are being lit at 22:00 local time in the Commonwealth and British overseas territories - those in the UK, Channel Islands and Isle of Man will be set alight between 22:00 and 22:30 BST.

Stars including McCartney and Wonder have been running through their sound checks on the concert stage, which has been set up around the Victoria Memorial in front of Buckingham Palace.

Meanwhile, groups of people without tickets began to arrive on The Mall nearby to watch the concert on big screens. They were only beaten to the best viewing spots by about 100 people who had set up tents overnight.

The event follows Sunday's spectacular River Thames pageant which attracted hundreds of thousands of rain-soaked people to watch the flotilla of 1,000 vessels as street parties took place across the country.

Picnic hampers for the guests arrived at the palace in the morning in a convoy of eight lorries after being assembled in Leicester overnight.

In the afternoon, the 10,000 winners of a public ballot and 2,000 VIPs and people from charities, will enjoy the picnic created by celebrity chef Heston Blumenthal and royal chef Mark Flanagan.

Individual hampers handed out to each of the guests will contain tea-smoked Scottish salmon, chilled garden soup, a coronation chicken-inspired dish, and strawberry crumble made from fruit grown on the Queen's Sandringham estate.

There will also be cupcakes created by Fiona Cairns, who baked the Duke and Duchess of Cambridge's wedding cake.

A union jack flag and plastic poncho, in case of rain, will also be included - but the forecast is for drier weather than on Sunday and temperatures of about 12C.

At Constitution Hill, picnic guests turning up to Buckingham Palace to see if they can queue to enter the grounds are being told to return later. But about 200 are choosing to remain in the area, milling around with other ticket holders near security barriers next to the entrance gate.

Thousands of people are expected in central London later to watch the concert on the big screens, which are also located in St James's Park, Hyde Park and Trafalgar Square.