At least three people have been killed and dozens injured in a series of grenade explosions in the business district of Bangkok.

The blasts came as hundreds of pro-government demonstrators were staging a rally in the Thai capital to call for an end to weeks of mass protests by the anti-government "Red Shirts".

The city was hit by five blasts, which sent panicked people running through the streets and fleeing an elevated train station.

Army spokesman Colonel Sansern Kaewkamnerd said five M-79 grenades were fired from grenade launchers.

Three fell through the roof of the Saladaeng Skytrain station in the centre of Bangkok's business district.

A fourth exploded on the pavement near the five-star Dusit Thani Hotel and the fifth near a bank, he said.

Thailand's deputy prime minister confirmed at least three people had been killed and 75 wounded, including four foreigners.

He also said the government had no plans to crack down on the protesters because there were women and children among them.

The Reds, who accuse the government of being undemocratic and elitist, have fortified their rally base in central Bangkok with barricades made from bamboo poles and piles of car tyres.

Hundreds of fully armed troops have poured into the area since Monday to keep the protesters from marching into the business district.

British tourist Liz Beswick, from Bournemouth, said the situation in Bangkok was "horrible".

She said: "There were people in red everywhere which was really intimidating.

"If you're not wearing red you stand out like a sore thumb and everyone stares at you.

"I was pretty scared to be honest."

:: The Foreign Office has changed its travel advice for Bangkok because of the risk of violence breaking out without warning.

Britons should avoid all but "essential" travel to the Thai capital, the Government said.

The Prime Minister says Nick Clegg and David Cameron "should take as much time as they feel necessary" to agree on a coalition deal.

Watch election coverage live on Sky Player, including a statement from David Cameron.

Gordon Brown went on to say if the two leaders could not come to an understanding, he was willing to speak to Mr Clegg, whose position he "completely respects".

With the General Election resulting in a hung Parliament - the first since 1974 - party leaders are attempting to form a stable administration.

In the first foray into deal-making, the Prime Minister earlier said he had asked the civil service to provide support for talks between parties.

But arriving back in London from his Sheffield Hallam seat, Mr Clegg said: "I think it is now for the Conservative Party to prove that it is capable of seeking to govern in the national interest."

The Conservatives said Mr Cameron would announce his intentions on how to form a government "that is strong and stable with broad support" at 2.30pm today.

The Prime Minister, speaking outside Number 10, said it was his responsibility to make any government work for the national good.

"David Cameron and Nick Clegg should clearly be entitled to take as much time as they feel necessary," he said.

"For my part, I should make clear, I would be willing to see any of the party leaders.

"Should the discussions between David Cameron and Nick Clegg come to nothing, I would be prepared to discuss with Nick Clegg the areas where there may be some measure of agreement between our two parties."

Mr Brown also made it clear the business of government would continue - with Alistair Darling to meet with EU finance ministers tonight over the Greece's economic crisis.

During a dramatic night in British politics, the Conservative leader claimed Labour had lost its "mandate to govern".

But Business Secretary Peter Mandelson appealed for patience and indicated there may not be a resolution until Monday.

"[The Prime Minister] has to stay at his post, we have to wait for the results and that will become clear during the course of the day," he told Sky News

"If it is a hung parliament... then either there has to be a minority government that takes its chance, or a combination of other parties - in this case - most like the Labour Party and the Liberal Democrats, would have to see whether they could form some arrangement instead.

"We are not at that stage yet. We have to be patient and wait for the final results."

After campaign polls suggested the Liberal Democrats would experience a surge in voter support, the party failed to realise their electoral dream.

Mr Clegg conceded: "We simply haven't achieved what we hoped."

However, the Lib Dem leader remains a 'kingmaker' in any discussions of a potential coalition.

He indicated this morning one of the most important issues for his party was the "broken" electoral system that had delivered a hung parliament.

"It simply doesn't reflect the hopes and aspirations of the British people," Mr Clegg said.

"I will continue to argue not only for the greater fairness in British society, not only the greater responsibility in economic policy making, but also for the extensive real reforms that we need to fix our political system."

Elsewhere, the Scottish National Party have ruled out doing business with the Conservatives but said they would be open to talking with Labour.